The present disclosure discloses a method, system, and apparatus for filtering packets. The method includes setting packet filtering information that uniquely identifies the basic characteristics of a media stream in an Internet Protocol version 6 (IPv6)-based packet header. As an apparatus for filtering packets, a media gateway (MG) uses the packet filtering information sent by the media gateway controller (MGC) to filter packets for the media stream when transferring the media stream. The method, system, and apparatus enable packet filtering for the media streams in an IPv6-based PS network. Moreover, the filtering conditions in the packet filtering information in the present disclosure is triplet information that uniquely identifies the basic characteristics of a media stream and can be obtained from the IPv6 packet header, thus reducing the complexity of the packet filtering process.