diff --git a/rules/prometheus.go b/rules/prometheus.go
index fa7255d..e270cca 100644
--- a/rules/prometheus.go
+++ b/rules/prometheus.go
@@ -39,6 +39,13 @@ var (
 		Help:      "etcd rules engine work buffer wait time in ms",
 		Buckets:   []float64{1, 2, 5, 10, 20, 50, 100, 200, 500, 1000, 2000, 5000, 10000, 30000, 60000, 300000, 600000},
 	}, []string{"method", "pattern"})
+	rulesEngineCallbackWaitTime = prometheus.NewHistogramVec(prometheus.HistogramOpts{
+		Name:      "callback_wait_ms",
+		Subsystem: "etcd",
+		Namespace: "rules",
+		Help:      "etcd rules engine callback wait time in ms",
+		Buckets:   []float64{1, 2, 5, 10, 20, 50, 100, 200, 500, 1000, 2000, 5000, 10000, 30000, 60000, 300000, 600000},
+	}, []string{"pattern"})
 )
 
 func init() {
@@ -47,6 +54,7 @@ func init() {
 	prometheus.MustRegister(rulesEngineEvaluations)
 	prometheus.MustRegister(rulesEngineWorkerQueueWait)
 	prometheus.MustRegister(rulesEngineWorkBufferWaitTime)
+	prometheus.MustRegister(rulesEngineCallbackWaitTime)
 }
 
 func incLockMetric(methodName string, pattern string, lockSucceeded bool) {
@@ -68,3 +76,7 @@ func workerQueueWaitTime(methodName string, startTime time.Time) {
 func workBufferWaitTime(methodName, pattern string, startTime time.Time) {
 	rulesEngineWorkBufferWaitTime.WithLabelValues(methodName, pattern).Observe(float64(time.Since(startTime).Nanoseconds() / 1e6))
 }
+
+func callbackWaitTime(pattern string, startTime time.Time) {
+	rulesEngineCallbackWaitTime.WithLabelValues(pattern).Observe(float64(time.Since(startTime).Nanoseconds() / 1e6))
+}
diff --git a/rules/prometheus_test.go b/rules/prometheus_test.go
index 490db7c..645656e 100644
--- a/rules/prometheus_test.go
+++ b/rules/prometheus_test.go
@@ -66,3 +66,8 @@ func TestWorkBufferWaitTime(t *testing.T) {
 	workBufferWaitTime("getKey", "/desired/key/pattern", time.Now())
 	checkMetrics(t, `rules_etcd_work_buffer_wait_ms_count{method="getKey",pattern="/desired/key/pattern"} 1`)
 }
+
+func TestCallbackWaitTime(t *testing.T) {
+	callbackWaitTime("/desired/key/pattern", time.Now())
+	checkMetrics(t, `rules_etcd_callback_wait_ms_count{pattern="/desired/key/pattern"} 1`)
+}
diff --git a/rules/worker.go b/rules/worker.go
index e159b41..92f999b 100644
--- a/rules/worker.go
+++ b/rules/worker.go
@@ -2,6 +2,7 @@ package rules
 
 import (
 	"sync"
+	"time"
 
 	"go.uber.org/zap"
 )
@@ -100,7 +101,9 @@ func (bw *baseWorker) doWork(loggerPtr **zap.Logger,
 	workerQueueWaitTime(metricsInfo.method, metricsInfo.startTime)
 	bw.metrics.WorkerQueueWaitTime(metricsInfo.method, metricsInfo.startTime)
 	if sat && !is(&bw.stopping) {
+		startTime := time.Now()
 		callback()
+		callbackWaitTime(metricsInfo.keyPattern, startTime)
 	}
 }