The invention discloses a method for mapping a unified parameter. The method is used for a communication device in a network system. The communication device comprises a media access control abstraction sublayer used for integrating a plurality of media. The method comprises the steps of obtaining the unified parameter and a parameter value of the unified parameter from an upper-layer communication protocol layer of the media access control abstraction sublayer, obtaining a media type of a media access control layer from a lower-layer media access control layer of the media access control abstraction sublayer, judging a special parameter used for setting the media type of the media access control layer and a format of the special parameter according to the media type and the unified parameter of the media access control layer, and generating a parameter value of the special parameter according to the parameter value of the unified parameter and the format of the special parameter.