To overcome the difficulty of deep buried tunnel microseismic source positioning and low positioning accuracy problems

a heuristic algorithm

gravitational search algorithm (GSA)

is used to in this paper to search the location. The algorithm is compared with results of the particle swarm optimization and the simplex algorithm. Research shows that

under the two and three velocity models

the gravitational search algorithm has the advantages of fast convergence and high precision over the particle swarm optimization and the simplex algorithm. The distance from the source location can be controlled within 10 m

which meets the need of tunnel construction better. For the two velocity model

the accuracy of gravitational search algorithm is 83.71 percent higher than the simplex

and 7.77 percent higher than the particle swarm optimization. For the three velocity model

the accuracy of gravitational search algorithm is 70.67 percent higher than the simplex

and 39.36 percent higher than the particle swarm optimization. Through the analysis

gravitational search algorithm (GSA) can provide a new idea for the position of micro-seismic source in deep buried tunnels.