To compare the effect of intermittent tramadol dosing vs tramadol administration via patient-controlled pump on pain after lumbar discectomy. This randomized prospective study enrolled 100 patients who underwent elective LIV-LV lumbar discectomy in the neurosurgery department at Sestre Milosrdnice University Hospital Center from May 2016 to July 2017. Patients were randomized to receive either tramadol (600 mg daily) via a patient-controlled analgesia (PCA) pump or intermittently. Pain was evaluated by the Croatian version of Short-Form McGill Pain Questionnaire. Forty percent of patients were women. The median (interquartile range) age of the patients was 51 (40-61) years. The groups did not differ in pain at 7 pm on the day of discectomy. However, in the morning and evening on the first postoperative day and in the morning and evening of the second postoperative day, the PCA group had significantly lower pain (P=0.023, P<0.001, P<0.001, P=0.026, respectively). This is the first study that used the Short Form McGill Pain Questionnaire to compare the effect of tramadol administration via PCA pump and intermittent administration on pain after LIV-LV discectomy in a neurosurgery department. Tramadol showed a good analgesic efficacy in lumbar spine surgery; tramadol via PCA controlled pain more effectively than intermittently administered tramadol.