Objective: To analyze postoperative therapeutic effects of patients with fractured anterior cruciate ligament (ACL) that underwent autologous tendon reconstruction at early and late period. Methods: A total of 60 patients underwent autologous tendon reconstruction were enrolled and retrospectively analyzed via arthroscopes from December, 2015 to December, 2017 in our hospital, in which 30 patients treated with ACL reconstruction within 6 weeks of injury were selected as the early reconstruction group (Group A), and the other 30 cases with ACL reconstruction between 6 weeks and 6 months were as late reconstruction group (Group B); the therapeutic effect of early and late ACL reconstruction was analyzed by recording and comparing of several indexes, such as knee lysholm score, knee IKDC score, intraoperative hemorrhage, operation time, pre-and post-operative range of motion (ROM) of the knee, etc. Results: The pre-and post-operative lysholm scores and IKDC scores were compared between the two groups, without statistically significant results (P > 0.05). The knee ROM scores of the late reconstruction group were higher than those of the early group (P < 0.05), and the intraoperative blood loss in the late stage was less than that in the early group (P < 0.05), which exhibits that the short-term clinical efficacy of early and late arthroscopic autologous tendon reconstruction for knee ACL injury was similar, but the late reconstruction group was with less intraoperative bleeding, and better postoperative joint mobility recovery; in conclusion, it is recommended that patients can be operated between 6 weeks and 6 months after injury.