Abstract: When in-seam wave encounters discontinuous section, such as fault, it will generate reflection and be received by geophone placed in the same tunnel with shot point, which can be used to detect the geological anomaly in the side of tunnel. In normal case, reflected in-seam wave has the disadvantage of weak energy and low signal-to-noise ratio. To raise the signal-to-noise ratio of reflected channel wave, this paper apply the enveloped superposition imaging method on the detection of reflected in-seam wave. Besides, the data of 3D numerical simulation and mining verified case also proves the effectiveness of reflected in-seam wave envelop superposition imaging.