The effects of different types and dosages of expanders on the early shrinkage， fluidity， and strength after hardening of cement based grouting material were studied. The results show that after adding sulphoaluminate expander， the late expansion effect of cement based grouting material is better， but its early expansion effect is not ideal. After the calcium oxide expander is incorporated， both early and late expansion effects are improved， but it has adverse effects on its fluidity and strength. Plastic expander can significantly increase the vertical expansion rate of slurry in the plastic stage， but has a great influence on the early strength of cement based grouting material. Adding defoaming agent into the cement based grouting material with the plastic expander can effectively reduce the size of air bubbles and improve its pore structure on the premise of ensuring the expansibility，and it also has a great effect on improving the strength and achieving a better comprehensive technical effect.