AB: Five puppies were presented at Alfort National Veterinary School, France, between December 1998 and 1999, for rapidly expanding, well-demarcated, subcutaneous cervical mass of a few days' duration. In all cases, previous trauma were reported. Fine-needle aspiration of the mass revealed a serosanguineous fluid containing mainly erythrocytes, and with a total protein concentration ranging from 3.5 to 5.2 g/dl. Coagulation tests failed to reveal any coagulation disorder. En-bloc surgical removal of the fluid-filled mass associated with short-term postoperative drainage was curative in all cases. Histopathological examination of the mass revealed encapsulated haematoma. The disease resembles chronic expanding haematoma in humans.