Widget updating method and system as well as Widget client and Widget server

The invention relates to Widget updating method and system as well as a Widget client and a Widget server. The method comprises the following steps that: the Widget client sends an update request to the Widget server; after receiving the update request, the Widget server extracts the current version of application package and the latest version of application package and compares the two application packages; the Widget server constructs a response body and sends the response body to the Widget client, wherein the response body comprises an update document constructed according to the comparison result and a preset update policy; and the Widget client receives the response body and is updated according to the update document. The invention can realize a part of updating and increases updating efficiency.