Abstract: The effects of mixing time in grouting process of we tground cement on motrar properties were studied.The results showed that high speed mixing time(Tg),wetgrinding time(Ts) and lowspeed mixin gime(Td) all have effects on properties of cement paste with different d egree.At last,the optimum controlling times of wetground cement were given and the microstructure test of hardened cement mortar was analysed.