Seventy-two patients with subacute or chronic rupture of the anterior cruciate ligament were randomly assigned to autograft reconstruction with four-strand gracilis and semitendinosus tendon (N = 37) or with patellar tendon-bone (N = 35) from the ipsilateral side. The groups were similar in terms of age, sex, level of activity, degree of laxity, meniscal lesions found surgically, and rehabilitation program. The follow-up was performed at another hospital by independent observers after 6, 12, and 24 months. Sixty-one patients (32 with hamstring tendon grafts and 29 with patellar tendon grafts) complied with the follow-up routine for the full 24 months. No differences were found between the groups with respect to Cincinnati functional score, KT-1000 arthrometer measurements, or stairs hopple test results. The subjective result and the single-legged hop test result were better for the hamstring tendon group after 6 and 12 months, but no differences were found after 24 months. The hamstring tendon group showed better isokinetic knee extension strength than did the patellar tendon group after 6 months, but not after 12 and 24 months. There was a significant weakness in isokinetic knee flexion strength among the hamstring tendon group. Anterior knee pain was not significantly different between the groups, but kneeling pain was significantly less common in the hamstring tendon group after 24 months.