Introduction: The aim of this study was to compare the effect of adding neostigmine to ropivacaine and sufentanil to ropivacaine in spinal anesthesia for hernia surgery. Materials and Methods: In this double-blind clinical trial study, 105 patients who were candidates for herniorrhaphy in Valiasr Hospital in Arak were included in the study and were divided into three groups of 35 based on block randomization method. In all patients, we used 0. 5% ropivacaine 3 ml (15 mg) for spinal. In the first group, patients received 50 micrograms of neostigmine, in the second group, patients received 5 micrograms of sufentanil and in the third group, patients received 1 ml of intrathecal distilled water. Sensory-motor block and pain were recorded in recovery at 1, 2, 4, 6 and 12 hours after surgery and the amount of opiod used. Data were analyzed by SPSS 20 software. Results: At 105 and 120 minutes after the start of surgery in the sufentanil group, the heart rate was lower than in the neostigmine group (P = 0. 027). The placebo group was the smallest (P = 0. 0001). However, there was no statistically significant difference between the two groups of sufentanil and neostigmine in terms of time elapsed until the onset of sensory and motor block or duration of sensory and motor block (P> 0. 05). Except for recovery, the pain was higher in the placebo group than in the other two groups (P = 0. 0001). But no statistically significant difference was observed between the two groups of sufentanil and neostigmine (P <0. 05). The amount of opiod used was higher in the placebo group (P = 0. 0001). But there was no statistically significant difference in the amount of opioid used between the two groups (P <0. 05). Conclusion: In general, it can be concluded that in terms of the severity of sensory and motor block and the amount of postoperative pain and the need for postoperative opioid use in the two groups of sufentanil and neostigmine, no significant difference was observed in the doses used in our study. Both drugs can be used as adjuvants with ropivacaine in spinal anesthesia for hernia surgery, depending on the preferences of the anesthesiologist and the availability of either drug.