The material for this study comprised 5 dogs between the ages of 5-9 months and 1 cat aged 1.5 years brought to the I.U. Veterinary Faculty Surgery Department Clinic between the years 1996-2005, with the inability to use their hindleg. The cases were presented to the clinic within a few days following the occurence of the lesion. Case histories revealed the causes to be jumping from a height in 4 animals and unknown in 2. A diagnosis of avulsion fracture of the tibial tuberosity was reached following clinical and radiological examination of the cases. Surgical intervention was carried out in all cases, of which fixation was achieved with a screw application in 5 cases and the tension band method using double Kirschner pins and cerclage wire in 1 case. In the clinical and radiographical follow-up approximately 2-4 month after the operation the trouble-free recovery of the patients was established in the light of the information given by the patient owners. There was no problem with respect to the limbs bearing weight in any of the cases. Therefore, no need was seen to remove the fixation material. In conclusion, the authors hope that it will be beneficial to veterinary practice to present the successful results achieved in the fixation of avulsion fracture of the tibial tuberosity using screws in 5 cases and the tension band method in 1 case, as well as reporting the rarely encountered lesion in cats.