The invention discloses a web system performance analysis method and device. The method comprises the steps of when a Web system does not meet the performance needs of a user, selecting an application component from the application components of the Web system as the test subject to conduct an iterative stress test; analyzing the performance of the Web system during each test of the application component, after it is determined that a performance bottleneck appears, optimizing the application component; when the application component completes the iterative stress test, conducting a stress test in mixed scenes, determining whether the Web system meets the performance needs of the user; when the Web system still cannot meet the performance needs of the user, based on the pre-established performance bottleneck distribution model, selecting the next application component from the application components of the Web system as a new test subject for the iterative stress test. The technical scheme can increase the test efficiency, shorten the performance cycle, and reduce the test cost.