Abstract: Turbine efficiency is a key parameter for turbine performance. The discharge measurement plays an important role in the field tests of turbine efficiency due to many test points and difficulties in operation. Therefore, the common test methods, principles and comprehensive errors of discharge measurement were introduced in this paper. Particularly, we expounded on the principles, field application, test results and precautions of relative method and ultrasonic method that were applied in the Pelton turbines of Moinak Hydropower Station. In addition, some specific research associated with the operation of Moinak Hydropower Station was conducted. The results show that the thermodynamics method and the intrusive ultrasonic flowmeter are not appropriate for Moinak Hydropower Station. Instead, the relative method and the clamp-on ultrasonic flow meter might work. At last, the relative method and the clamp-on ultrasonic flow meter were successfully used in accurate discharge measurement of pipelines with large diameter and thickness. The test results were highly recognized by the owner of Kazakhstan.