diff --git a/pulsar/internal/utils.go b/pulsar/internal/utils.go
index 0763cedcb4..e4a4994a3e 100644
--- a/pulsar/internal/utils.go
+++ b/pulsar/internal/utils.go
@@ -28,6 +28,10 @@ import (
 
 // TimestampMillis return a time unix nano.
 func TimestampMillis(t time.Time) uint64 {
+	// calling UnixNano on the zero Time is undefined
+	if t.IsZero() {
+		return 0
+	}
 	return uint64(t.UnixNano()) / uint64(time.Millisecond)
 }
 
diff --git a/pulsar/internal/utils_test.go b/pulsar/internal/utils_test.go
index 65babd04e9..90d6f2d5b3 100644
--- a/pulsar/internal/utils_test.go
+++ b/pulsar/internal/utils_test.go
@@ -55,3 +55,8 @@ func TestParseRelativeTimeInSeconds(t *testing.T) {
 	assert.Nil(t, err)
 	assert.Equal(t, time.Duration(10)*time.Hour*24*7*365, timestamp)
 }
+
+func TestTimestampMillis(t *testing.T) {
+	assert.Equal(t, uint64(0), TimestampMillis(time.Time{}))
+	assert.Equal(t, uint64(7), TimestampMillis(time.Unix(0, 7*int64(time.Millisecond))))
+}