Objective: This experimental study was performed to investigate the effect of pentoxyfylline on retinal nitric oxide levels in the ischemia/reperfusion injury in a guinea pig model.Materials and Methods: In this study, three groups of five pigmented guinea pigs were formed; control, sham and the treatment (Pentoxyfylline) groups. Pressure induced 90 minutes of retinal ischemia and 24 hours of reperfusion were established in the sham and treatment groups. Saline for sham group and 45 mg/kg of Pentoxyfylline for treatment group were administered intraperitoneally in three times with eight hours intervals. At the end of the reperfusion period both eyes of the animals of all groups were enucleated. One eye of each animals were randomly selected for biochemical assay and retinal nitrate levels were measured and we calculated the arithmetical averages and SD for each group. Statistical analysis was performed with Mann-Whitney U test, p values< 0.05 were considered significant.Results: The mean retinal nitrate levels of the control, sham and treatment groups were 153.4±23.13 µmol/gr wet tissue, 112.6±17.03 µmol/gr wet tissue and 137.8±16.49 µmol/gr wet tissue respectively. Nitrate levels decreased significantly in sham group than control and treatment groups (p<0.01, p<0.05). Nitrate levels of treatment group and control group were found similar (p>0.05).Conclusion: Pentoxyfylline that shows a protective effect in retinal ischemia reperfusion injury kept retinal nitric oxide levels stable in our study, this may make it a potential alternative agent for the prevention of retinal ischemiareperfusion injury.