On the basis of the theory of grey connection analysis, the correlation between the qualities and crack resistance of cement is experimentally studied. The results show that the content of C^₂S, which affects the crack resistance of cement maximally, has a positive interconnection with the crack resistance of cement, and the content of C^₃S has a negative interconnection. The sequence of factors that affect the cracking time of cement paste is C^₂S content>specific surface area >C^₃A content>C^₃S content>C^₄AF content.