The main topic of inter-domain routing security management is how to suppress the propagation of untrustworthy routes and malicious routing behaviors. Supervising and evaluating autonomous system’s (AS)routing behaviors is a key technology in this topic. This paper designs a distributed collaborative reputation mechanism of trustworthiness evaluation for AS’s routing behaviors. The mechanism takes in the statistical results on routing trustworthiness published by AS, uses a self-organizing method, employs posterior probability analysis,and finally calculates a reputation score for a particular AS. The score will be used as a metric on the trustworthiness of the routing information that AS propagates or announces afterwards. In simulations, this reputation mechanism has been shown to effectively contain AS’s bad behaviors, and hence improve the overall security of the inter-domain system. The reputation mechanism designed in this research supplies a reference to evaluation and analysis of AS’s routing behaviors. It has the following features: It supports incremental deployment.It needn’t modify the BGP protocol, so it is easy to be implemented.