Abstract: In view of problem that positioning accuracy drops sharply when seismic source is placed in far-field, a far-field seismic source positioning method based on improved GA algorithm was proposed. The improved GA algorithm makes use of fast convergence speed of quasi-Newton method and global search of GA algorithm to realize seismic source positioning. Simulation results show that the improved GA algorithm runs about three times faster than the GA algorithm. In view of problem that positioning accuracy of y-axis cannot be guaranteed due to uniaxial arrangement of sensors, it was proposed to change the position of the sensors to two axes and set independent sub-objective functions on both axes to minimize the biaxial error. Analysis results show that the new objective function converges faster and runs more stably, and can effectively improve y-axis positioning accuracy.