Purpose: To evaluate and compare the functional results, activity status, and anterior stability between conservative group with partial ACL injury and reconstruction group with bone-patellar ten-don-bone autograft in ACL total rupture. Materials and Methods: Thirty-eight patients with ACL injury were diagnosed and treated with arthroscopy and followed for more than two years. The number of patients with partial injury was 12(mean age; 38.3) and reconstruction group was 26 (mean age; 25.3). Objective stability was estimated under anterior loading of 15 lb and 20 lb by KT-2000 Arthrometer (MED metric, USA). Functional evaluation using Lysholm score and Tegner activity score were performed. Results: Average functional score of Lysholm was 88.5 in partial injury group and 89.3 in reconstruction group. Average score of Tegner was 5.3 in partial injury group and 5.1 in reconstruction group(P<0.05).Average anterior displacement compared with normal side. Under loading of 20lb, 1.7$pm$4.3 mm in partial injury group, 2.3$pm$1.9 mm in reconstruction group were anterior displaced (P<0.05). Under loading of 15lb, 1.2$pm$1.0 mm in partial injury group, 1.4$pm$1.5 mm in reconstruction group were dis-placed (P<0.05). There were giving way, effusion, instability and anterior knee pain in complication. Giving way was the frequent complication in the partial injury group. Conclusions: Clinical results of both group were similar. Functional evaluation of Lysholm was good and status of Tegner activity was maintained to physical fitness activites (jogging, regular bik-ing) in both groups on average. The results of conservative treatment for the partial ACL injury (less than 50$\%$) was satisfactory and equivalent to that of reconstructive treatment for the total ACL injury.