diff --git a/libfprint/fp-device.c b/libfprint/fp-device.c
index 13f1b5a..b2190bd 100644
--- a/libfprint/fp-device.c
+++ b/libfprint/fp-device.c
@@ -382,6 +382,7 @@ fp_device_finalize (GObject *object)
 
   g_clear_pointer (&priv->device_id, g_free);
   g_clear_pointer (&priv->device_name, g_free);
+  g_clear_object (&priv->usb_device);
 
   G_OBJECT_CLASS (fp_device_parent_class)->finalize (object);
 }