Abstract: At present there are thirty-one third-party certification authorities obtaining a license of electronic certification services in China. The trust and verification schemes between CAs are becoming increasingly urgent. A trusted third party inter-domain authentication model based on trust lists is proposed to solve the existing problem. To overcome the shortcomings of traditional trust lists model, the proposed model utilizes the digital certificate security services provided by public key infrastructure, better manages and controls the trusted root certificate lists through the new trust mechanism. Furthermore, the proposed model can effectively realize multi-CA mutual trust and mutual recognition. We design the work-flow and multi-CA authentication scheme, develop the supporting system to support real realization of multi-CA mutual trust and mutual recognition, and also present the key techniques in details in this paper. Analysis shows that the proposed model can facilitate application systems’ dynamic compatibility to the digital certificates issued by different certification authorities. And it has obvious advantages at authentication efficiency, safety, practicability, application of transformation and Etc.