The invention provides a method and a system for testing performances of an ESB (enterprises service bus) platform. The method includes steps receiving a first configuration instruction, loading a service request script corresponding to a script identity in the first configuration instruction from a request script library, and configuring access information and access parameters of the corresponding service request script according to configured parameters of the first configuration instruction; receiving a second configuration instruction, and obtaining a calling way of a corresponding request method from a request method library; receiving a third configuration instruction, and sending configuration information in the third configuration instruction to a corresponding stimulator in a stimulator library for configuring; performing performance testing to the ESB platform according to the service request script and the calling way after which are being configured and the configured stimulator; collecting tested data during performance testing and performance data of a server corresponding to the ESB platform; and obtaining testing results according to the tested data and the performance data. By the method and the system, performances of the ESB platform can be obtained accurately, efficiently, conveniently and quickly.