We compared the effect of midazolam sedation with or without fentanyl on the hemodynamic parameters, sedation, and pain and satisfaction profile in cataract surgery. Two hundred and ten patients were randomly allocated to receive either midazolam 1 mg i.v. (Group M, n = 101) alone or with fentanyl 25 microg (Group MF, n = 100) before retrobulbar injection. Hemodynamic parameters, observer's assessment of alertness/sedation (OAA/S) scores, pain during block and surgery, satisfaction of patient and surgeons were assessed. Heart rate and diastolic arterial pressure decreased after retrobulbar injection in comparison to baseline whereas systolic arterial pressure values increased in both groups. The majority of patients in both groups experienced mild pain during retrobulbar injection but no pain during surgery. There was a significant decrease in OAA/S scores in both groups (p = 0.001) and this decline was more significant in Group MF (p = 0.038). We suggest that midazolam alone may produce optimal block conditions for the patient and it is satisfactory during the procedure while the addition of fentanyl has not improved the effect on the examined parameters.