An embodiment of the invention discloses a method for accounting processing, which comprises the following steps: sending accounting request containing user device access information of media resources to accounting system by business server, wherein at least two or more user device; executing accounting processing according to user device access information of media resources in accounting request by accounting system; returning accounting response to business server after accounting processing by accounting system. Accordingly, the embodiment of the invention also discloses a network system, accounting system and business server. The technical scheme in the embodiment of the invention can realize accounting when user uses a plurality of user device to process business in session.