Abstract: There are many methods in detection of grouting quality in mine cavities. However, there are no mature and credibility technical methods. This paper introduces a method combining DC sounding and Electromagnetic CT techniques. The two techniques operate simply and could reflect the grouting quality of cavities in detail. The combined method has applied to the detection of grouting quality in mine cavities along a railway The results indicate that the grouting quality is well at the segment K0+278～K0+45. The results of the two techniques are consistency. It is proved that the combined method is reasonable and feasible for detecting the grouting quality at mine cavities. The case study in this paper can provide experience for testing other homogeneous reinforce effect.