Abstract:AIM: To detect the presence of 8-hydroxydeoxyguanosine enzyme (8-OHdG) in recurrent pterygium and its role on recurrence. METHODS: Ninty-two samples were collected of which 55 from primary pterygium, 12 from recurrent and 25 from normal conjunctiva. A cross sectional study was embarked to detect the presence of the 8-OHdG enzyme in primary, recurrent pterygium and the normal conjunctival tissue by immunohistochemistry test. RESULTS: The immunohistochemistry test showed positive results: 35 in primary, 2 in recurrent pterygia and 4 in normal conjunctiva, respectively. Significant association between primary pterygium and 8-OHdG enzyme (63.6% of samples are positive) and no significant relation was detected with recurrent pterygium (16.7% of samples are positive). CONCLUSION: 8-OHdG enzyme is associated with primary pterygium. It is also present in normal conjunctival tissue. For the first time it is detected in recurrent pterygia. This may raise question whether 8-OHdG enzyme has a role in recurrence of pterygium.