The present invention provides a method for resolvablly accessing detection prefix and collision prefix of base station in packet transmission chanel of WCDMA system. According to the accessed resource information broadcast by common packet channel state indication channel CSICH the terminal can select the useful accessed resource and give out AP to request access; according to the possible rangeof CD prefix recorded in front period of time the base station can discriminate type of accessed prefix, if the received prefix is fallen in the possible range of CD prefix, it can be disciminated into CD, other is AD. The base station can predict AP prefix which is mixed with CD prefix to be received, and can define its range, and the accessed resource which is broadcast by CSICH channel of the syste and is correspondent to AP is unusable, the base station can make other treatment. It can raise voltage of common packet channel.