Background:Postoperative urinary retention-a common and important complication of surgical procedures, can occur after any form of surgical intervention, in both sexes and all ages regardless of patients’ previous history of urinary problems. The importance of post operative urinary tract retention is due to its effect on development of post operative urinary infection, patient anxiety and discomfort, prolongation of hospital stay and increase in hospital costs and morbidity. The International Prostate Symptom Score (IPSS) is an easy method for quantifying and estimating the association between pre-operative bladder-outflow problems and post-operative urinary retention. The aim of present study was to investigate whether the IPSS could predict the likelihood of patients developing urinary retention after elective cataract surgery.Methods:One hundred and fourteen male patients older than fifty years old, who were candidate for elective cataract surgery, were enrolled in this study. All patients completed an IPSS questionnaire form before operation, and classified into three groups regarding their score (0-7: mild, 8-19: moderate, 20- 35: severe).Results:Totally 8 patients (7%) developed post-operative urinary retention during first 24 hours after operation. Of the 8 urinary retention patients, 2 had moderate symptoms and 6had severe symptoms. There was a significant difference in developing postoperative urinary retention between patients having mild symptoms and patients having severe symptoms (P-value: 0.025).Conclusion:It is concluded that while some litterateurs definitely support the idea that IPSS may be useful for predicting post operative urinary retention, there are still some controversies. Considering our results, it seems that IPSS score is not useful in the accurate prediction of those patients who are likely to develop postoperative retention after surgical procedures other than arthroplasty, and more precise studies are need to be conducted about urinary retention occurring postoperatively in different type surgeries, different methods of anesthesia considering age and gender of patients.