The water cooling heatsink (WCH) and the plate-fin heat exchanger (PFHE) are the two core heat exchange components in the water-cooling system. The thermal performance test for the WCH and the PFHE is a normal type test. Usually, WCH and PFHE were separately tested in two different professional test platforms under normal conditions. On the basis of the similarities and differences between the test conditions of the WCH and PFHE, a multifunctional integrated test platform that can be compatible with WCH and PFHE was developed in this paper, which could be compliantly used for performance testing of water cooling system, and be helpful for the verification of the parameter in the water cooling system. According to the data of a validating test case, the relative error of the coolant flux was less than 1%, the relative temperature error was less than 2%, and the relative error of the temperature rise and flow resistance test results of the application case was less than 5%.