The invention discloses a three-dimensional comprehensive testing device for an internal flow field of hydraulic impeller machinery. By the three-dimensional comprehensive testing device for the internal flow field of the hydraulic impeller machinery, the problems that the accuracy and the calculation efficiency of the overall-field-domain speed field, which is measured by the existing testing device for an internal flow field of hydraulic impeller machinery, of the internal flow field of the impeller machinery are not high, and the temperature information and the pressure information of the internal flow field of the impeller machinery cannot be obtained synchronously are solved. The three-dimensional comprehensive testing device for the internal flow field of the hydraulic impeller machinery comprises a visual hydraulic impeller machinery system, an optical testing system and a water circulating system, wherein the visual hydraulic impeller machinery system comprises a visual hydraulic torque converter; the optical testing system comprises an optical measuring rack and is arranged right above the visual hydraulic torque converter through an optical measuring rack; two optical measuring rack bases of the optical measuring rack are arranged on a foundation and on two sides of the visual hydraulic torque converter; the water circulating system comprises a flowmeter and a water storage tank; an outlet end of the flowmeter is connected with a water medium inlet pipeline on an oil sleeve of the visual hydraulic torque converter; and a water inlet of the water storage tank is connected with a water medium outlet pipeline on the oil sleeve of the visual hydraulic torque converter.