This paper analyzes the characteristic and distribution pattern of casing damage in the round, adopts many methods and techniques to systemically investigate the essential characteristic natural fracture and modern in-situ stress of Saertu, Putaohua, Gaotaizi reservoirs in the west of Daqing Placanticle and what they have done to casing damage, further analyzes the main effecting geological factors that result in casing damage in this region. This paper points out that the main internal causes are the open and glide of fracture face effected by in-situ stress, put forward two preventive measures to control the fracturing scale and maintaining national water injection pressure, to prevent casing damage.