During a Cesarean section of a bitch on the 68th day of gestation multiple cauliflower structures in the uteral wall and perforation of the uterus were diagnosed. Two immature dead foetuses were found in the body cavity outside of the uterus. One foetus was joined to the placenta by means of an umbilical cord. Gross pathology and microscopic analysis of histological slices of the uterus wall enabled to diagnose pathological lesions in the dog as a mole (mola hydatidosa destruens).