Abstract: In order to determine the stope stability of line 85 to line 88 at -616 mlevel of No.2 ore body of Dayingezhuang，its joint fissures are measured.According to the joint occurrence，and through the DIPS software，it is obtained that there are two dominant sets of joint with the structural plane of NE-SW in strike.The inclination and orientation of the two dominant joints are 41° and 316°，58° and 146° respectively.Based on site investigation，the rock mass are classified according to the value of Q.It is concluded that 7 stopes from line 85 to line 86.5 has a better stability，4 stopes from line 86.5 to line 87.5 is in general and No.7106 stope at line 88 is worse.With a reliable conclusion，the study provides the reference and the basis for the zoning of parameters optimization.

Key words: Joint fissures, Classification of rock mass, Stability of stope, Classification