The aim of this study was to compare the effect of flunixin meglumine (FM) and meloxicam (M) on postoperative and oxidative stress in ovariohysterectomized bitches. Twenty four bitches were divided into three groups (n=8 in each) and treated during premedication as follows: FM (2.2 mg/kg, iv, Fluvil, Vilsan, Turkey), M (0.2 mg/kg, sc, Maxicam, Sanovel, Turkey) or 0.9% saline (1 ml, iv, IE, Turkey) - control (C) group. The concentrations of serum cortisol, nitric oxide (NO), malondialdehyde (MDA), antioxidant potential (AOP) and glutation (GSH) were measured in blood samples collected during incision (0 h), closure of incision line (0.5 h) and 1, 2.5, 12 and 24 hours after incision. It was observed that cortisol level was higher at 0.5, 1 and 2.5 h in group C (p < 0.05), 0.5 h in group FM (p < 0.001), and 1 and 2.5 h in group M (p < 0.01), as compared to that determine at 0 h. Group C showed higher cortisol level during 0.5 h (p < 0.05) than that found in the other groups. Group FM displayed lower levels during 1 h (p < 0.01) and 2.5 h (p < 0.05) as compared to those observed in other groups. Concentrations of MDA, AOP and GSH between all the groups did not show any significant differences. MDA level was higher at 0.5 and 1 h in groupM (p < 0.05) than that found in group C and it was the lowest at 2.5 h in group C (p < 0.05). AOP was higher at 2.5 h in group FM and M (p < 0.05) than that observed in group C, and at 12 and 24 h in group M than that found in group C and FM. GSH did not show any significant differences between the groups. NO level in group FM after 12 h was higher (p < 0.05) than that at 0.5, 1 and 24 h. Moreover, NO level was lower at 0.5 (p < 0.01), 1 (p < 0.05) and 24 h (p < 0.05) in group FM than that observed in group C and M. In conclusion, flunixin meglumine decreases cortisol and NO levels more efficiently than meloxicam. Therefore, it is suggested that postoperative stress following ovariohysterectomy may be prevented by flunixin meglumine in bitches.