Abstract: In order to explore a new method to realize the stable measurement of the flow in the variable backwater area of the reservoir, and improve the accuracy of the flow measurement in the area, this paper took Wusheng Hydrological Station in the middle and lower reaches of Jialing River as the research object, analyzed the applicability of H-ADCP in the flow measurement of variable backwater area by comparing the synchronous measured data of Horizontal Acoustic Doppler Current Profiler (H-ADCP) and traditional rotary current meter.The results showed that the calibration verification results of the proposed piecewise unary linear regression model scheme were good and met the requirements of the first-class accuracy station specification.However, the distortion of H-ADCP results caused by high sediment concentration and large flow velocity needs to be supplemented by rotary current meter.During equipment installation, the H-ADCP representative velocity relationship can maintain the coverage capacity in dry season by considering the operating water level of the downstream Lize Navigation Hub.The linear regression model for H-ADCP flow measurement in backwater areas can provide a technical reference for similar stations in mountainous rivers.