·AIM:To investigate the efficacy and safety of postoperative 90Sr β-irradiation for patients with pterygium and analyze the recurrence-related factors.·METHODS:Between May 2006 and September 2008,seventy-nine patients with 93 pterygium eyes were treated with surgery and postoperative 90Sr β-irradiation.After doing bare sclera technique of pterygium excision,postoperative 90Sr β-irradiation was carried out.A total dose of 2400 cGy dose was used in three fractions(800 cGy,each time,one week apart).At the cut off time(three months),the recurrence rate was calculated and compared between male and female,young(<40 years)and old(≥40 years),fresh and relapsing pterygium.·RESULTS:Recurrence of the pterygium treated with surgery and postoperative 90Sr β-irradiation was observed in 7 of 93(7.5%)cases.Recurrence-related factors analysis revealed that younger age(<40 years),relapse cases were risk factors for local recurrence.Complications noted were few:including moderate conjunctivitis,postoperative pain,photophobia and an increase in tear flow.However,no long-term serious side effects were observed in this study,such as scleral necrosis or radiation cataract.·CONCLUSION:Bare sclera technique of pterygium excision followed by fractioned 90Sr β-irradiation is a safe and effective therapy to prevent a relapse and can be performed without serious side effects.The study also showed several factors might influence the therapy efficacy,such as age and previous surgical treatment.·