Abstract: To explore the influence of grouting materials on strengthening coal and rock mass structure, controlling coal and rock deformation and preventing coal and gas outburst, high performance grouting material (HGC), micro expansion and high performance grouting material (EHGC), ordinary portl and cement (OPC) and sulphoaluminate cement (SAC) were used to prepare four different grout-coal composite samples. Through uniaxial compression and electron microscope scanning tests, the strength characteristics of different grout-coal samples and the microstructure characteristics of grout-coal interface were analyzed. The results show that the compressive strength of HGC sample is the highest, and the peak strength of EHGC sample is 10.98% lower than that of HGC. The failure modes of OPC and SAC specimens are tensile shear failure, HGC specimens are tensile failure, and EHGC specimens are tensile splitting failure, with the smallest degree of failure. The scanning electron microscope (SEM) results show that the cementation form of HGC, OPC and SAC with coal rock is covered, and there are cracks in the interface area of grout-coal. The cementation form of EHGC and coal rock is embedded type. The micro-porosity of OPC sample is the largest, followed by SAC, and HGC is the smallest. The micro-porosity of EHGC is 6.93% higher than that of HGC.