Using the WRF (Weather Research and Forecasting) model and the MWRT (Microwave Radiative Transfer) model, this paper simulated the cloud precipitation process of an ideal convective cell, and studied the influence of graupel spectrum parameters on the brightness temperature of high-frequency microwave radiation of strong convective precipitation cloud.Results show that the changes of graupel spectrum parameters have effects on the mass concentration distribution of ice phase hydrometeors and the high frequency microwave brightness temperature in convective cell cloud.Decreasing (increasing) of graupel density parameter will increase (decrease) the width of graupel spectrum, strengthen (weaken) the collision-coalescence growth efficiency of graupel, increase (decrease) the maximum mass concentration of graupel, and reduce (increase) the maximum mass concentration of ice crystal and snow, finally the minimum brightness temperature decreases (increases).Increasing (decreasing) of graupel shape parameter will increase (decrease) the width of graupel spectrum, increase (decrease) the maximum mass concentration of graupel, and decrease (increase) the maximum mass concentration of ice crystal and snow, finally the minimum brightness temperature decreases (increases) in the simulation area.In addition, the sensitivity of regional minimum brightness temperature to different graupel spectrum parameters or different changes of the same graupel spectrum parameters is different.