Disclosed are a uterine cavity implant, a preparation method and the use thereof. The uterine cavity implant has a bag-shaped structure, and comprises a substrate material of an animal small intestine submucosa having been subjected to a decellularization treatment. The uterine cavity implant is prepared by subjecting the substrate material to tissue pre-processing, virus inactivation, washing, decellularization in a multi-frequency ultrasonic device, washing, vacuum freeze-drying, and a molding step. The uterine cavity implant is used in uterine cavity-implanted medical instruments, and can treat and prevent intrauterine adhesion, and improve the decellularization process for a biological repair material, so that the uterine cavity implant has a lower quantity of residual DNA, lower immunogenicity, stronger anti-infection capacity and stronger repair capacity; and same is beneficial for the recovery of tissues, such as the uterine cavity basal layer, submucosa and mucous layer. The uterine cavity implant, as a built-in uterine cavity structure, is used for isolating wound surfaces, repairing uterine cavity tissues and reducing scar formation, so that the problem of intrauterine adhesion is solved, and the problem of sterility caused by same can also be solved.