A media negotiation method for an IP multimedia link is used in the process of establishing an IP multimedia link between a first entity and a second entity via an application server (AS) of an IP multimedia subsystem (IMS). AS sends the second entity an invite message, which includes media resource information of the first entity; When AS receives a message with media resource information from the second entity before an answer message is received or after it receives a response message with media resource information from the second entity, AS sends an IMS re-invite message without media source information to the first entity; the AS, after receiving the IMS signaling message with media resource information from the first entity, sends the first entity the media resource information returned by the second entity. The present invention is applicable to an IMS centralized service and may effectively reduce the number of steps and the time required after response for media resource re-negotiation.