This invention relates to a method for protecting high layer service in the multi-layer communication equipment, include that low layer processing module which provides low layer transmission passages for high layer processing module, and high layer processing module which sets up transparent VP link passage from up and down node by the service of said module, in order to make the service processed by the said module avoid influence. Once detecting the fault of the said processing module, high layer processing module will message the low layer processing module, and the low layer processing module will set up bypass connection after detecting the fault of the high layer processing module, then isolate the failed high layer process module. According to the present invention, extra network passages are not necessary, the means of protecting network is not limited. The present invention aims to protect effectively ATM traffic when the processing ability of ATM layer invalidate between MSPP and MSTP. The present invention solves the problem that will influence the other node of the network beyond the said node service in the case of device maintenance.