The seismic waveform of Yutian MS7. 3 earthquake，Xinjiang on February 12，2014 was recorded clearly and completely by the Digital Seismic Networks of Xinjiang，Qinghai，Tibet， and Xinjiang Hotan array，so the method of joint positioning by regional seismic network and seismic array can be used to accurately determine the earthquake source location． The following technologies were used in the process of positioning: (1) We selected seismic stations equally located around epicenter of MS7. 3 earthquake with average intervals of about 15 degrees in the initial positioning． (2) The recording waveform of Yutian seismic station was rotated to the radial and tangential to precisely obtain the arrival time of S-wave to control the epicentral distance． (3) Velocity model was used in the determination of the epicenter，based on the historical records of earthquakes in the area within a radius of 1. 0° from the source as the center，and the velocity model is obtained after re-fitting and calibration． (4) Based on the Hotan seismic array recording waveform，the method of waveform beaming for the determination of the azimuth is used，and the epicenter location was determined with this azimuth． (5) The deterministic method was used to measure the source depth． Finally，it is concluded that the Yutian MS7. 3 main shock hypocenter location was 36. 197°N，82. 467°E，focal depth of 12km，original time of February 12，2014 (17:19:48. 2pm)．