One of the advantages of intravenous regional anesthesia is rapid return of normal sensation and power of movement at the end of the surgery. The aim of the present study is to compare the effect of different doses of granisetron in combination with lidocaine in intravenous regional anesthesia. In this double blind clinical trial, from May 2014 to July 2015, ninety patients who were candidate for forearm Orthopedic surgeries entered the study. Patients in the first group received 0.5% lidocaine (3 mg/kg), one mg granisetron in the second group, and also 2 mg granisetron in the third group in combination with 0.5% lidocaine (3 mg/kg). Pain during surgery and after it was assessed using visual analog scale. The results showed that mean pain of patients immediately after the inflation of tourniquet and at minutes 15, 30 and 45 in the third group was significantly lower than the other two groups (p=0.0001) and also the difference between granisetron groups(second & third groups) and first group was significant. The average time of onset of tourniquet pain was 33.50±7.56 minutes in the first group, 41.33±4.96 minutes in second, and 44.70±4.39 minutes in the third group and this time in both granisetron groups (second & third groups) was significantly higher than first group (p=0.0001). It seems that using granisetron can significantly reduce the pain during and after forearm surgery.