The dropping point of a projectile is an important parameter for evaluating the range weapon performance. A Bayesian jointed source location method by using seismic and acoustic observations is developed. This jointed method is to take advantage of signals in the atmosphere and seismic wave signals in the ground and reduce the influence of atmospheric factors, geological factors, topographical factors, and seismic phase identification factors on the location accuracy. Therefore, it is a high-precision location method. Firstly, this paper combined the four-element cross acoustic array and the single seismic measurement points to measure the acoustic signals/seismic waves of the surface explosion. Then, the paper obtained the azimuth information through sound arrays and signal arrival information through the seismic measurement points and performed an inversion of the explosive source location based on the Bayesian theory. The results show that the Bayesian location method has a high precision due to the full consideration of the error model and a-priori information. In addition, the Bayesian jointed source location method can provide more constraints on the location of the explosive source by integrating seismic wave data and acoustic data, which makes the probability density distribution of the explosive source more concentrated and the location result more robust.