Incisional local anaesthesia is widely used for postoperative pain relief after surgery. We present the results of a double-blinded and randomised controlled study of incisional bupivacaine versus placebo in 68 children undergoing open appendectomy. The trial medicine (0.5 ml/kg) was infiltrated into the subcutis after wound closure. Patients with a weight below 40 kg received a bupivacaine concentration of 0.25 % and the patients above 40 kg a concentration of 0.5 %. During the first 24 hours after surgery the patients in the bupivacaine group received on average 0.065 mg morphine/kg and in the placebo group 0.073 mg/kg. This difference was not statistically significant. The patients in the bupivacaine group tended to experience pain relief for a longer period of time compared to the patients in the placebo group. However, the difference was not significant. In conclusion, the use of subcutaneous infiltration with bupivacaine in the wound after open appendectomy had no significant effect on the use of morphine during the first postoperative day in children.