An apparatus and method for assisting in delivering update contents in computer networks are provided. The computer networks also comprise at least one peer client, and the assistant apparatus comprises: an evaluating unit configured to evaluate a user's interaction preference according to the user's interaction history; and a prefetching unit configured to evaluate, in response to the received update notification, whether to prefetch the update contents corresponding to the update notification according to the evaluated interaction preference, and, if prefetching, obtain the update contents from at least one peer client. The corresponding method is also provided. With the apparatus and method in this invention, the update contents in computer networks can be delivered between peer clients, not via the server, which reduces the server load without impairing user experience on client side.