The dead reckoning was originally used for ship positioning in sailing,the cost of the used accelerometer, magnetic compass and gyroscope is high and those size is big.With the development of MEMS technology,the size,weight and cost of accelerometer,digital compass and gyroscope are greatly reduced.So it can be applied in pedestrian navigation.According to the principle of the dead reckoning, GPS/INS tightly integrated navigation system INS 1200 can be ued to conduct navigation experiment, collect realtime data.Experimental data is solved according to the dead reckoning and coordinate transformation algorithm.The positioning maps after coordinate transformation are simulated by MATLAB.The simulation result shows that the dead reckoning owns higher navigation accuracy in short time.There is greater significance for navigation in short time.