Through synthetic data tests, the influence on source location results of surface and downhole recording systems are discussed, as well as the combination of both. The results indicate that joint use of surface and downhole recording systems can significantly improve the location accuracy. With the downhole recording system, the location results obtained by adopting different objective functions in source location algorithm are compared. Moreover, a new objective function is also proposed. The effectiveness of the new objective function is tested on synthetic and real data sets. The results demonstrate that this objective function shows better convergency in both horizontal and vertical directions, and it can produce more reliable location results.