To implement blast source localization precisely by the lowest number of sensor nodes, we propose a time delay of arrival (TDOA) localization method with time synchronization estimation algorithm based on spatial overpressure sensing system (SOSS) using low-power wide-area network (LPWAN) in this paper. The proposed SOSS consisting of an internal spatial wireless sub-array (ISWS) and external wireless planar sub-arrays (EWPS) is to combine the angle with distance to assess the blast source location by the least average error approximation algorithm. The ISWS is used to calculate the incoming angle of blast source towards the central point of the SOSS, while the EWPS calculates the distance from the central of the SOSS to the blast source. We have also proved that the time synchronization algorithm has an obvious impact on the blast range estimation error calculation. The results in the proposed method show that the localization distance and angle error of blast source is within 1 m and 1°in 2D coordinates, respectively. This paper is conducted to provide new insight into blast source localization algorithm and explore how time synchronization of WSN affects localization precision.Index Terms: Blast wave, Overpressure, Time synchronization, LPWAN, WSN.