diff --git a/mastodon_test.go b/mastodon_test.go
index 69e520e..9c2f2ac 100644
--- a/mastodon_test.go
+++ b/mastodon_test.go
@@ -190,3 +190,37 @@ func TestGetAccountFollowing(t *testing.T) {
 		t.Fatalf("want %q but %q", "bar", fl[0].Username)
 	}
 }
+
+func TestRegisterApp(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != "POST" {
+			http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
+			return
+		}
+		if r.URL.Path != "/api/v1/apps" {
+			http.Error(w, http.StatusText(http.StatusNotFound), http.StatusNotFound)
+			return
+		}
+		if r.FormValue("redirect_uris") != "urn:ietf:wg:oauth:2.0:oob" {
+			http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
+			return
+		}
+		fmt.Fprintln(w, `{"client_id": "foo", "client_secret": "bar"}`)
+		return
+	}))
+	defer ts.Close()
+
+	app, err := RegisterApp(&AppConfig{
+		Server: ts.URL,
+		Scopes: "read write follow",
+	})
+	if err != nil {
+		t.Fatalf("should not be fail: %v", err)
+	}
+	if app.ClientID != "foo" {
+		t.Fatalf("want %q but %q", "foo", app.ClientID)
+	}
+	if app.ClientSecret != "bar" {
+		t.Fatalf("want %q but %q", "bar", app.ClientSecret)
+	}
+}