The present invention discloses a method for implementing cross-domain resource management. If requesting for service connection resources, for each domain, a border Call Agent (CA) first sends a connection resource request to a specific bearer network resource manager in its domain. This bearer network resource manager decides whether the destination user's device is in its administration domain. If yes, it makes an appropriate processing and returns a response of a successful processing to the CA it belongs to; if not, the bearer network resource manager performs an appropriate preprocessing and sends back a response of a successful preprocessing to the CA it belongs to, and after receiving the response, the CA sends a connection resource request to its next-hop CA.