Abstract: A system, device and method for carrying out policy-based routing mode are provided; the system in this invention contains database, for storing multiple routing policies set by user, and storing one of the routing policy as current routing policy; communication server, inquiring current routing policy of the user in the database in calling process, and implementing calling based on current routing policy. The system also contains Web server, which receives multiple routing policies of user, and sends them to the database. This invention carries out that the user relies on multiple policies to guide system to flexibly select routing calling through the different user attributes as routing policy evidences, which reaches the aim of enriching uniform communication service content and improving uniform communication service quality.