Abstract: Concealed hazard sources in the working face are the main hidden danger for safe production in the coal mines, and the Radar Travel Time Tomography technology can realize the high-precision detection of the concealed hazard source in the large-span working face.This paper puts forward an evaluation criteria for tomographic accuracy, including the evaluation indicators of variance of velocity difference between inversion velocity field and actual velocity field, deviation degree of the inversion center of the anomalous body, and deviation degree of the size of the anomalous body.Then the influence of radar traveling time tomography by point spacing, transmitting angle and inversion grid in mine is analyzed through forward modeling, resulting in the optimized parameters for observation system and inversion.Finally, the optimized parameters are employed to carry out some field verification experiments, and the results show that the anomalous body can be detected affectively for the working face within 100 m span, providing effective technical support for the rapid and precise detection of concealed hazard sources in large-span working face in mine area.