Abstract: Space positioning techniques by using GPS can give high re-lative positioning precision(10~(-6)～10~(-8)),and is a new method to monitorcrustal movement and forecast the earthquake.North China is an activeseismic region where earthquake frequency and its intensity are high.Byusing GPS,an earthquake monitoring network is established in NorthChina.Based on meticulous observation,optimum design and close adjust-ment,a first group of results with high precision are obtained.Establi-shing of GPS network in North China will form an important scientificbasis forecasting of heavy earthquake and studing of the earth.