Abstract: The purpose of this investigation is to illustrate the effects of receiver antenna snow accumulation on GPS phase observables.Firstly,the effects of snow cover on carrier phase signal field strength and power are analyzed.Then a simplified model is developed to estimate GPS phase propagation delay due to the complicated mixing ratio of snow and resultant complex refractivity.The theoretical analysis revealed that the magnitude of propagation delay,which can be significant in high-accuracy GPS applications,depends on satellite elevation,the water content of snow and snow depth.At last,the daily coordinates of two stations with ten continuous days of GPS observations are estimated using precise point positioning technology.The results indicate that antenna snow cover have an effect on the antenna phase center,and induce horizontal and vertical errors of several centimeters or even more.