Our objective was to study the analgesic effect of acupoint pressure on postoperative pain in a controlled single-blind study. Forty patients undergoing knee arthroscopy in an ambulatory surgery unit in a university-affiliated hospital were randomized to receive either an active stimulation (AS) or a placebo stimulation (PS) 30 min after awakening from anesthesia. We stimulated 15 classical acupoints in the AS group, on the side contralateral to surgery, with a firm pressure and a gliding movement across the acupoint. In the PS group, 15 nonacupoints were subjected to light pressure in the same areas as the acupoints in the AS group. We assessed pain using a 100-mm visual analog scale (VAS) before sensory stimulation, after 30 and 60 min, and after 24 h. We recorded heart rate, systolic arterial pressure, and skin temperature before stimulation and after 30 and 60 min. We assessed skin blood flow with laser Doppler before stimulation and after 1 and 30 min. Sixty minutes and 24 h after AS, VAS pain scores were lower than in the placebo group (p < 0.05 and 0.0001, respectively). There were no significant changes in the autonomic variables. The results indicate that pressure on acupoints can decrease postoperative pain.