Methods, systems, and computer readable media for answer-based routing of Diameter request messages are disclosed. According to one method, a Diameter request message is received from a first Diameter node at a. A copy of at least a portion of the Diameter request message is cached at the DSR and the Diameter request message is routed to a second Diameter node. The DSR determines whether a predetermined condition associated with an answer to the first Diameter request message exists. In response to determining that the predetermined condition exists, the cached portion of the Diameter request message is retrieved, a Diameter request that includes the cached portion of the Diameter request message is generated, and the generated Diameter request message is routed.