Abstract: Weathering agency can result not only in vaviation of physical components and chemical components of rock, but also in change of joints and integrality of rock mass in the weathering process. Therefore, a better correlation exists between amounts of joints and block size in rockmass and degree of weathering. In this paper, the weathering zones are distinguished in accordance with joint spacing, integrality index of rock mass and rock quality index and in combination with rock mass structure and its engineering properties. A quantitative classification of weathering zones is carried out and good results are also obtained in the paper.