diff --git a/client.go b/client.go
index cd849d4..3fe3db2 100644
--- a/client.go
+++ b/client.go
@@ -157,6 +157,7 @@ type Usage struct {
 	Data   [][]float64 `json:"data"`
 }
 
+// オブジェクトストレージへのリクエスト数を取得
 func (cc *ConohaClient) ObjectStorageRequests() (map[string]float64, error) {
 	// メトリクス取得
 	resp, err := cc.get(cc.accountEndpoint + "/object-storage/rrd/request")
@@ -185,6 +186,7 @@ type ObjectStorageSizeResponse struct {
 	Size Usage `json:"size"`
 }
 
+// オブジェクトストレージの使用容量を取得
 func (cc *ConohaClient) ObjectStorageUsage() (map[string]float64, error) {
 	// メトリクス取得
 	resp, err := cc.get(cc.accountEndpoint + "/object-storage/rrd/size")
@@ -227,8 +229,8 @@ type Database struct {
 	Type             string  `json:"type"`
 }
 
+// データベース一覧取得
 func (cc *ConohaClient) Databases() ([]*Database, error) {
-	// データベース一覧取得
 	resp, err := cc.get(cc.databaseHostingEndpoint + "/databases")
 	if err != nil {
 		return nil, err
@@ -259,9 +261,9 @@ type Quota struct {
 	Quota      int     `json:"quota"`
 }
 
-func (cc *ConohaClient) DatabaseQuota(d *Database) (*Quota, error) {
-	// データベース使用容量/上限値取得（GB単位）
-	resp, err := cc.get(cc.databaseHostingEndpoint + "/services/" + d.ServiceID + "/quotas")
+// データベース上限値取得（GB単位）
+func (cc *ConohaClient) DatabaseQuota(serviceID string) (*Quota, error) {
+	resp, err := cc.get(cc.databaseHostingEndpoint + "/services/" + serviceID + "/quotas")
 	if err != nil {
 		return nil, err
 	}
@@ -274,3 +276,24 @@ func (cc *ConohaClient) DatabaseQuota(d *Database) (*Quota, error) {
 
 	return &uResp.Quota, nil
 }
+
+// JSON 受け取り用
+type DatabaseInfoResponse struct {
+	Database Database `json:"database"`
+}
+
+// データベース情報取得（GB単位）
+func (cc *ConohaClient) DatabaseInfo(databaseID string) (*Database, error) {
+	resp, err := cc.get(cc.databaseHostingEndpoint + "/databases/" + databaseID)
+	if err != nil {
+		return nil, err
+	}
+
+	// JSONを読む
+	var uResp DatabaseInfoResponse
+	if err := json.Unmarshal(resp, &uResp); err != nil {
+		return nil, err
+	}
+
+	return &uResp.Database, nil
+}
diff --git a/exporter.go b/exporter.go
index 1a57e48..992965f 100644
--- a/exporter.go
+++ b/exporter.go
@@ -32,7 +32,7 @@ func NewConohaCollector(client *ConohaClient) (*ConohaCollector, error) {
 			// 4番目のnilには、固定ラベルをprometheus.Labelsで渡せる
 			prometheus.NewDesc("object_storage_requests", "Requests to Object Storage", []string{"method"}, nil),
 			prometheus.NewDesc("object_storage_usage", "Usage of Object Storage", []string{}, nil),
-			prometheus.NewDesc("database_usage", "Usage of Database Server (GB)", []string{"database"}, nil),
+			prometheus.NewDesc("database_usage", "Usage of Database (GB)", []string{"database"}, nil),
 		},
 		[]prometheus.Metric{},
 		databases,
@@ -56,13 +56,26 @@ func (cc *ConohaCollector) AutoUpdate() {
 		usage, err := cc.ObjectStorageUsage()
 		metrics = append(metrics, prometheus.MustNewConstMetric(cc.describes[1], prometheus.GaugeValue, usage["value"]))
 
+		serviceIDs := make(map[string]bool)
+
 		for _, db := range cc.databases {
 			// データベース使用状況を取得
-			quota, err := cc.DatabaseQuota(db)
+			info, err := cc.DatabaseInfo(db.DatabaseID)
+			if err != nil {
+				log.Fatal(err)
+			}
+			metrics = append(metrics, prometheus.MustNewConstMetric(cc.describes[2], prometheus.GaugeValue, info.DbSize, db.DbName))
+
+			serviceIDs[db.ServiceID] = true
+		}
+
+		for serviceID := range serviceIDs {
+			// データベース上限値取得
+			quota, err := cc.DatabaseQuota(serviceID)
 			if err != nil {
 				log.Fatal(err)
 			}
-			metrics = append(metrics, prometheus.MustNewConstMetric(cc.describes[2], prometheus.GaugeValue, quota.TotalUsage, db.DbName))
+			metrics = append(metrics, prometheus.MustNewConstMetric(cc.describes[2], prometheus.GaugeValue, float64(quota.Quota), "Quota "+serviceID))
 		}
 
 		// メトリクスデータ更新