diff --git a/internal/infra/github/gh_command.go b/internal/infra/github/gh_command.go
index 84d8c32..0013d7e 100644
--- a/internal/infra/github/gh_command.go
+++ b/internal/infra/github/gh_command.go
@@ -166,6 +166,16 @@ func GetSobaLabels() []CreateLabelRequest {
 			Color:       "e1e4e8",
 			Description: "New issue awaiting processing",
 		},
+		{
+			Name:        "soba:todo:high",
+			Color:       "d73a4a",
+			Description: "High priority task",
+		},
+		{
+			Name:        "soba:todo:low",
+			Color:       "cfd3d7",
+			Description: "Low priority task",
+		},
 		{
 			Name:        "soba:queued",
 			Color:       "fbca04",
diff --git a/internal/infra/github/label_test.go b/internal/infra/github/label_test.go
new file mode 100644
index 0000000..e88d7d2
--- /dev/null
+++ b/internal/infra/github/label_test.go
@@ -0,0 +1,74 @@
+package github
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestGetSobaLabels(t *testing.T) {
+	labels := GetSobaLabels()
+
+	// 既存のラベルが含まれていることを確認
+	expectedLabels := map[string]bool{
+		"soba:todo":             false,
+		"soba:todo:high":        false,
+		"soba:todo:low":         false,
+		"soba:queued":           false,
+		"soba:planning":         false,
+		"soba:ready":            false,
+		"soba:doing":            false,
+		"soba:review-requested": false,
+		"soba:reviewing":        false,
+		"soba:done":             false,
+		"soba:requires-changes": false,
+		"soba:revising":         false,
+		"soba:lgtm":             false,
+	}
+
+	// 全てのラベルが定義されていることを確認
+	assert.Equal(t, len(expectedLabels), len(labels), "ラベル数が一致しません")
+
+	// 各ラベルが正しく定義されていることを確認
+	for _, label := range labels {
+		if _, exists := expectedLabels[label.Name]; exists {
+			expectedLabels[label.Name] = true
+			// ラベルの色とdescriptionが設定されていることを確認
+			assert.NotEmpty(t, label.Color, "ラベル %s の色が設定されていません", label.Name)
+			assert.NotEmpty(t, label.Description, "ラベル %s の説明が設定されていません", label.Name)
+		}
+	}
+
+	// 全ての期待されるラベルが見つかったか確認
+	for name, found := range expectedLabels {
+		assert.True(t, found, "期待されるラベル %s が見つかりません", name)
+	}
+}
+
+func TestGetSobaLabels_Priority(t *testing.T) {
+	labels := GetSobaLabels()
+
+	// 優先度ラベルが正しく定義されているか確認
+	priorityLabels := map[string]struct {
+		expectedColor string
+		expectedDesc  string
+	}{
+		"soba:todo:high": {
+			expectedColor: "d73a4a", // 赤系の色（高優先度）
+			expectedDesc:  "High priority task",
+		},
+		"soba:todo:low": {
+			expectedColor: "cfd3d7", // グレー系の色（低優先度）
+			expectedDesc:  "Low priority task",
+		},
+	}
+
+	for _, label := range labels {
+		if expected, ok := priorityLabels[label.Name]; ok {
+			assert.Equal(t, expected.expectedColor, label.Color,
+				"ラベル %s の色が期待値と異なります", label.Name)
+			assert.Equal(t, expected.expectedDesc, label.Description,
+				"ラベル %s の説明が期待値と異なります", label.Name)
+		}
+	}
+}
\ No newline at end of file
diff --git a/internal/service/queue_manager.go b/internal/service/queue_manager.go
index d5d0d87..3cb4ff8 100644
--- a/internal/service/queue_manager.go
+++ b/internal/service/queue_manager.go
@@ -2,6 +2,7 @@ package service
 
 import (
 	"context"
+	"sort"
 	"strings"
 
 	"github.com/douhashi/soba/internal/infra/github"
@@ -54,8 +55,8 @@ func (q *QueueManager) EnqueueNextIssue(ctx context.Context, issues []github.Iss
 		return nil
 	}
 
-	// 3. 最小番号のIssueを選択
-	targetIssue := q.selectMinimumIssue(todoIssues)
+	// 3. 優先度順で最適なIssueを選択
+	targetIssue := q.selectPriorityIssue(todoIssues)
 
 	// 4. ラベル変更（soba:todo → soba:queued）
 	q.logger.Info(ctx, "Enqueueing issue", logging.Field{Key: "issue", Value: targetIssue.Number})
@@ -196,3 +197,56 @@ func (q *QueueManager) hasSobaLabel(issue github.Issue) bool {
 	}
 	return false
 }
+
+// getPriority はIssueの優先度を判定する（0:高、1:通常、2:低）
+func (q *QueueManager) getPriority(issue github.Issue) int {
+	hasHigh := false
+	hasLow := false
+
+	for _, label := range issue.Labels {
+		if label.Name == "soba:todo:high" {
+			hasHigh = true
+		} else if label.Name == "soba:todo:low" {
+			hasLow = true
+		}
+	}
+
+	// 複数の優先度ラベルがある場合は最高優先度を採用
+	if hasHigh {
+		return 0
+	}
+	if hasLow {
+		return 2
+	}
+	return 1 // デフォルトは通常優先度
+}
+
+// sortByPriority はIssueを優先度順にソートする
+func (q *QueueManager) sortByPriority(issues []github.Issue) []github.Issue {
+	sorted := make([]github.Issue, len(issues))
+	copy(sorted, issues)
+
+	sort.Slice(sorted, func(i, j int) bool {
+		priorityI := q.getPriority(sorted[i])
+		priorityJ := q.getPriority(sorted[j])
+
+		if priorityI != priorityJ {
+			return priorityI < priorityJ // 優先度が高いほど値が小さい
+		}
+
+		// 同じ優先度の場合はIssue番号順
+		return sorted[i].Number < sorted[j].Number
+	})
+
+	return sorted
+}
+
+// selectPriorityIssue は優先度を考慮して最適なIssueを選択する
+func (q *QueueManager) selectPriorityIssue(issues []github.Issue) *github.Issue {
+	if len(issues) == 0 {
+		return nil
+	}
+
+	sorted := q.sortByPriority(issues)
+	return &sorted[0]
+}
diff --git a/internal/service/queue_manager_priority_test.go b/internal/service/queue_manager_priority_test.go
new file mode 100644
index 0000000..72a349f
--- /dev/null
+++ b/internal/service/queue_manager_priority_test.go
@@ -0,0 +1,332 @@
+package service
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/mock"
+
+	"github.com/douhashi/soba/internal/infra/github"
+	"github.com/douhashi/soba/pkg/logging"
+)
+
+func TestQueueManager_getPriority(t *testing.T) {
+	qm := &QueueManager{
+		logger: logging.NewMockLogger(),
+	}
+
+	tests := []struct {
+		name     string
+		issue    github.Issue
+		expected int
+	}{
+		{
+			name: "高優先度のIssue",
+			issue: github.Issue{
+				Number: 1,
+				Labels: []github.Label{
+					{Name: "soba:todo:high"},
+					{Name: "soba:todo"},
+				},
+			},
+			expected: 0, // 最高優先度
+		},
+		{
+			name: "通常優先度のIssue",
+			issue: github.Issue{
+				Number: 2,
+				Labels: []github.Label{
+					{Name: "soba:todo"},
+				},
+			},
+			expected: 1, // 通常優先度
+		},
+		{
+			name: "低優先度のIssue",
+			issue: github.Issue{
+				Number: 3,
+				Labels: []github.Label{
+					{Name: "soba:todo:low"},
+					{Name: "soba:todo"},
+				},
+			},
+			expected: 2, // 低優先度
+		},
+		{
+			name: "高優先度と低優先度の両方を持つIssue（最高優先度を採用）",
+			issue: github.Issue{
+				Number: 4,
+				Labels: []github.Label{
+					{Name: "soba:todo:high"},
+					{Name: "soba:todo:low"},
+					{Name: "soba:todo"},
+				},
+			},
+			expected: 0, // 最高優先度を採用
+		},
+		{
+			name: "優先度ラベルがないIssue",
+			issue: github.Issue{
+				Number: 5,
+				Labels: []github.Label{
+					{Name: "bug"},
+				},
+			},
+			expected: 1, // デフォルトは通常優先度
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := qm.getPriority(tt.issue)
+			assert.Equal(t, tt.expected, result)
+		})
+	}
+}
+
+func TestQueueManager_sortByPriority(t *testing.T) {
+	qm := &QueueManager{
+		logger: logging.NewMockLogger(),
+	}
+
+	issues := []github.Issue{
+		{
+			Number: 5,
+			Labels: []github.Label{{Name: "soba:todo:low"}, {Name: "soba:todo"}},
+		},
+		{
+			Number: 2,
+			Labels: []github.Label{{Name: "soba:todo:high"}, {Name: "soba:todo"}},
+		},
+		{
+			Number: 4,
+			Labels: []github.Label{{Name: "soba:todo"}},
+		},
+		{
+			Number: 1,
+			Labels: []github.Label{{Name: "soba:todo:high"}, {Name: "soba:todo"}},
+		},
+		{
+			Number: 3,
+			Labels: []github.Label{{Name: "soba:todo"}},
+		},
+		{
+			Number: 6,
+			Labels: []github.Label{{Name: "soba:todo:low"}, {Name: "soba:todo"}},
+		},
+	}
+
+	sorted := qm.sortByPriority(issues)
+
+	// 優先度順に並んでいることを確認
+	// 高優先度（Issue 1, 2）
+	assert.Equal(t, 1, sorted[0].Number)
+	assert.Equal(t, 2, sorted[1].Number)
+
+	// 通常優先度（Issue 3, 4）
+	assert.Equal(t, 3, sorted[2].Number)
+	assert.Equal(t, 4, sorted[3].Number)
+
+	// 低優先度（Issue 5, 6）
+	assert.Equal(t, 5, sorted[4].Number)
+	assert.Equal(t, 6, sorted[5].Number)
+}
+
+func TestQueueManager_selectPriorityIssue(t *testing.T) {
+	qm := &QueueManager{
+		logger: logging.NewMockLogger(),
+	}
+
+	tests := []struct {
+		name           string
+		issues         []github.Issue
+		expectedNumber int
+	}{
+		{
+			name: "高優先度のIssueが優先される",
+			issues: []github.Issue{
+				{
+					Number: 10,
+					Labels: []github.Label{{Name: "soba:todo"}},
+				},
+				{
+					Number: 20,
+					Labels: []github.Label{{Name: "soba:todo:high"}, {Name: "soba:todo"}},
+				},
+				{
+					Number: 30,
+					Labels: []github.Label{{Name: "soba:todo:low"}, {Name: "soba:todo"}},
+				},
+			},
+			expectedNumber: 20, // 高優先度のIssue
+		},
+		{
+			name: "同じ優先度の場合はIssue番号が小さいものが選ばれる",
+			issues: []github.Issue{
+				{
+					Number: 15,
+					Labels: []github.Label{{Name: "soba:todo:high"}, {Name: "soba:todo"}},
+				},
+				{
+					Number: 10,
+					Labels: []github.Label{{Name: "soba:todo:high"}, {Name: "soba:todo"}},
+				},
+				{
+					Number: 20,
+					Labels: []github.Label{{Name: "soba:todo:high"}, {Name: "soba:todo"}},
+				},
+			},
+			expectedNumber: 10, // 同じ高優先度の中で最小番号
+		},
+		{
+			name: "通常優先度のみの場合",
+			issues: []github.Issue{
+				{
+					Number: 30,
+					Labels: []github.Label{{Name: "soba:todo"}},
+				},
+				{
+					Number: 10,
+					Labels: []github.Label{{Name: "soba:todo"}},
+				},
+				{
+					Number: 20,
+					Labels: []github.Label{{Name: "soba:todo"}},
+				},
+			},
+			expectedNumber: 10, // 最小番号
+		},
+		{
+			name: "低優先度のみの場合",
+			issues: []github.Issue{
+				{
+					Number: 25,
+					Labels: []github.Label{{Name: "soba:todo:low"}, {Name: "soba:todo"}},
+				},
+				{
+					Number: 15,
+					Labels: []github.Label{{Name: "soba:todo:low"}, {Name: "soba:todo"}},
+				},
+			},
+			expectedNumber: 15, // 低優先度の中で最小番号
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := qm.selectPriorityIssue(tt.issues)
+			assert.NotNil(t, result)
+			assert.Equal(t, tt.expectedNumber, result.Number)
+		})
+	}
+}
+
+func TestQueueManager_EnqueueNextIssue_WithPriority(t *testing.T) {
+	tests := []struct {
+		name             string
+		issues           []github.Issue
+		expectedIssueNum int
+		setupMock        func(*MockQueueGitHubClient, int)
+		shouldEnqueue    bool
+	}{
+		{
+			name: "高優先度のIssueが通常優先度より先に処理される",
+			issues: []github.Issue{
+				{
+					Number: 1,
+					Labels: []github.Label{{Name: "soba:todo"}},
+				},
+				{
+					Number: 2,
+					Labels: []github.Label{{Name: "soba:todo:high"}, {Name: "soba:todo"}},
+				},
+				{
+					Number: 3,
+					Labels: []github.Label{{Name: "soba:todo:low"}, {Name: "soba:todo"}},
+				},
+			},
+			expectedIssueNum: 2, // 高優先度のIssue
+			setupMock: func(m *MockQueueGitHubClient, issueNum int) {
+				m.On("RemoveLabelFromIssue", mock.Anything, "owner", "repo", issueNum, "soba:todo").Return(nil)
+				m.On("AddLabelToIssue", mock.Anything, "owner", "repo", issueNum, "soba:queued").Return(nil)
+			},
+			shouldEnqueue: true,
+		},
+		{
+			name: "高優先度が複数ある場合は番号が小さいものが優先",
+			issues: []github.Issue{
+				{
+					Number: 5,
+					Labels: []github.Label{{Name: "soba:todo:high"}, {Name: "soba:todo"}},
+				},
+				{
+					Number: 3,
+					Labels: []github.Label{{Name: "soba:todo:high"}, {Name: "soba:todo"}},
+				},
+				{
+					Number: 1,
+					Labels: []github.Label{{Name: "soba:todo"}},
+				},
+			},
+			expectedIssueNum: 3, // 高優先度の中で最小番号
+			setupMock: func(m *MockQueueGitHubClient, issueNum int) {
+				m.On("RemoveLabelFromIssue", mock.Anything, "owner", "repo", issueNum, "soba:todo").Return(nil)
+				m.On("AddLabelToIssue", mock.Anything, "owner", "repo", issueNum, "soba:queued").Return(nil)
+			},
+			shouldEnqueue: true,
+		},
+		{
+			name: "低優先度のみの場合でも正しく処理される",
+			issues: []github.Issue{
+				{
+					Number: 10,
+					Labels: []github.Label{{Name: "soba:todo:low"}, {Name: "soba:todo"}},
+				},
+				{
+					Number: 5,
+					Labels: []github.Label{{Name: "soba:todo:low"}, {Name: "soba:todo"}},
+				},
+			},
+			expectedIssueNum: 5, // 低優先度の中で最小番号
+			setupMock: func(m *MockQueueGitHubClient, issueNum int) {
+				m.On("RemoveLabelFromIssue", mock.Anything, "owner", "repo", issueNum, "soba:todo").Return(nil)
+				m.On("AddLabelToIssue", mock.Anything, "owner", "repo", issueNum, "soba:queued").Return(nil)
+			},
+			shouldEnqueue: true,
+		},
+		{
+			name: "アクティブタスクがある場合は優先度に関わらずスキップ",
+			issues: []github.Issue{
+				{
+					Number: 1,
+					Labels: []github.Label{{Name: "soba:planning"}},
+				},
+				{
+					Number: 2,
+					Labels: []github.Label{{Name: "soba:todo:high"}, {Name: "soba:todo"}},
+				},
+			},
+			expectedIssueNum: 0,
+			setupMock:        func(m *MockQueueGitHubClient, issueNum int) {},
+			shouldEnqueue:    false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			mockClient := new(MockQueueGitHubClient)
+			if tt.shouldEnqueue {
+				tt.setupMock(mockClient, tt.expectedIssueNum)
+			}
+
+			qm := NewQueueManager(mockClient, "owner", "repo")
+			qm.SetLogger(logging.NewMockLogger())
+
+			err := qm.EnqueueNextIssue(context.Background(), tt.issues)
+			assert.NoError(t, err)
+
+			mockClient.AssertExpectations(t)
+		})
+	}
+}