Abstract: This paper introduces the working principle of hemodialysis equipment tester, discusses the calibration method of the flow parameters in the hemodialysis equipment tester, studies and designs a small flow calibration device for the flow parameters calibration of the hemodialysis equipment tester, which is based on the liquid flow device of the static mass method, combined with the standard flowmeter as the measurement standard, and realizes the calibration of hemodialysis equipment tester calibration of flow parameters, the results show that calibration of standard flowmeter and analysis of the uncertainty of the device can meet the calibration requirements of flow parameters.