Aiming at the problem of the influence of seepage hysteresis effect on the accuracy of seepage monitoring models of earth-rockfill dams, considering the difference between the effect of reservoir water level and precipitation on the seepage flow of earth-rockfill dams under different hysteresis effects, the normal distribution function and Rayleigh distribution function were introduced to quantitatively describe the effect of reservoir water level and precipitation on the seepage lag, and a monitoring model of seepage pressure of earth-rockfill dam considering the lag effect was constructed. In order to solve the model parameters, based on the sparrow search optimization algorithm, the optimal values of the model hysteresis parameters and regression coefficients were obtained. Taking a core wall earth-rockfill dam as an example, the accuracy of the seepage monitoring model with and without considering different hysteresis effects were compared and analyzed. The results show that the seepage pressure monitoring model constructed in this study has higher accuracy, closer to the actual situation, and can quantitatively evaluate the hysteresis effect of seepage flow in earth-rockfill dams, which can be used for safety state evaluation of seepage flow and health monitoring of earth-rockfill dams. Keywords: earth-rockfill dam; seepage flow; monitoring model; hysteresis effect; sparrow search algorithm 〖FL