Non-steroidal anti-inflammatory drugs (NSAIDs) are a group of analgesics, which have been used in veterinary medicine progressively, especially in recent years. It has been reported that NSAIDs may be associated with adverse effects which lead to some concerns about their using in stressful conditions including surgery. The objective of this study was to evaluate potential adverse effects of ketoprofen following experimental tibial osteotomy in cats. To conduct the study 10 domestic short hair adult male cats were used. After restraining and routine preparation, the tibia of the right leg was exposed and separated using a gigli wire. Fixation was performed with intramedullary pin and fiberglass cast. After surgery, the animals received treatment of ketoprofen (2 mg/kg) or normal saline subcutaneously. Evaluation of the adverse effects of treatments in bone healing via radiographic analysis, gastric mucosa via endoscopic evaluation, and renal function and hemostasis via blood analysis, was done until 28^th day postoperatively. The results of this study showed a significant lower callus formation in ketoprofen group compared to saline (P < 0.05). Endoscopic evaluation, blood urea nitrogen (BUN) and creatinine, platelet count and bleeding time (BT) did not show any significant differences in both groups. Based on the results of this study it seems that ketoprofen could delay normal bone healing in experimental tibial osteotomy in cats. It is recommended to use ketoprofen in cats with more caution, especially after orthopedic surgeries.