diff --git a/mackerel-plugin-uptime/lib/uptime_test.go b/mackerel-plugin-uptime/lib/uptime_test.go
new file mode 100644
index 000000000..bdde1be3c
--- /dev/null
+++ b/mackerel-plugin-uptime/lib/uptime_test.go
@@ -0,0 +1,25 @@
+package mpuptime
+
+import "testing"
+
+func TestFetchMetrics(t *testing.T) {
+	var uptime UptimePlugin
+
+	stat, err := uptime.FetchMetrics()
+	if err != nil {
+		t.Fatal(err)
+	}
+	seconds := stat["seconds"]
+	if seconds <= 0 {
+		t.Errorf("invalid seconds value: %f", seconds)
+	}
+}
+
+func TestGraphDefinition(t *testing.T) {
+	var uptime UptimePlugin
+
+	graphdef := uptime.GraphDefinition()
+	if len(graphdef) != 1 {
+		t.Errorf("GetTempfilename: %d should be 1", len(graphdef))
+	}
+}