Ketoprofen (KTP) is a non-steroidal anti-inflammatory drug (NSAID) used as an analgesic, antipyretic and anti-inflammatory agent in human and veterinary medicine. Although KTP is used in the treatment of diseases such as musculoskeletal inflammation, endotoxemia, pneumonia, enteritis in sheep and minor surgical procedures such as dehorning and castration there is no information about its safety. The aim of this study is to determine the effect of KTP on biochemical and coagulation parameters following intramuscular (IM) administration of different doses of KTP to lambs. In the study, 18 clinically healthy lambs were randomly divided into three groups of 6 animals each. KTP was administered IM to lambs at doses of 1.5, 3 and 6 mg/kg. Biochemical and coagulation parameters were evaluated by taking blood samples before drug administration (0 hour) and at 24 hours and 48 hours after administration. No local or systemic side effects were observed in lambs after the administration of KTP at different doses. The aspartate aminotransferase (AST), creatine kinase (CK) and lactate dehydrogenase (LDH) values at 24 hours significantly increased compared to 0 hours in all dosage groups (p<0.05). KTP did not cause a significant change in albumin (ALB), alanine aminotransferase (ALT), blood urea nitrogen (BUN), creatinine (CRE), CK and LDH values in different dose groups. The AST value was only significantly higher in the 6 mg/ kg dose group compared to the 1.5 mg/kg dose group at 24 hours (p<0.05). Although there was no statistically significant difference in intragroup prothrombin time (PT), fibrinogen and D-dimer levels in all dose groups, a significant increase was observed in the activated partial thromboplastin time (aPTT) value of 6 mg/kg dose group at the 24 hours compared to the 0 hour (p< 0.05). As a result, after IM administration of 1.5, 3 and 6 mg/kg, increased CK and LDH values, which may be associated with muscle damage, may limit use of KTP via IM injection in lambs.