Background Patients who have undergone anterior cruciate ligament (ACL) reconstruction often experience balance dysfunction and decreased stability in posture control. However, there is a scarcity of clinical studies on the correlation of posture control abilities after ACL reconstruction both domestically and internationally.Objective To analyze the physiological and psychological factors affecting the postural control ability in patients after ACL reconstruction.Methods Patients enrolled in the Department of Rehabilitation Medicine, the First Medical Center of Chinese PLA General Hospital, who underwent ACL reconstruction surgery and satisfied the inclusion criteria at ≥6 months postoperatively from January 1, 2021 to July 31, 2024, were designated as the ACL reconstruction group. Age- and sex-matched healthy volunteers currently employed at the hospital served as the healthy control group. Both groups were assessed using one-leg standing tests, Y-balance tests, VAS scale, IKDC scale, TSK-11 scale, Tegner scale, and ACL-RSI scale. Comparisons and correlation analyses were performed between test performance and subjective scales. Results A total of 25 male participants were enrolled in each group. There were no statistically significant differences in age (28.64±4.93 vs 26.64±4.17), or height between the two groups (P > 0.05). However, both body weight and body mass index (BMI) were significantly greater in the ACL reconstruction group compared to the control group (P < 0.01). The evaluation time for patients in the ACL reconstruction group was (16.04 ± 12.41) months postoperatively. The ACL reconstruction group had higher levels of pain at rest (1.56±1.85 vs 0±0), pain during movement (4.20±2.58 vs 0±0), and TSK-11 score (26.80±7.08 vs 16.40±5.39) compared to the control group (P<0.01). The Tegner score (4.24±1.45 vs 7.64±1.78), IKDC score (65.84±15.29 vs 97.84±2.39), and ACL-RSI score (59.68±25.25 vs 112.92±10.14) were lower in the ACL reconstruction group than in the control group (P<0.01). There was no significant difference in one-leg standing test performance between the ACL reconstruction group and the control group (P>0.05). The ACL reconstruction group's Y-balance test composite score for the left lower limb (0.82±0.11 vs 0.76±0.08) was better than that of the control group (P<0.05). The difference in composite Y-balance scores for both lower limbs (0.03 (-0.01, 0.14) vs 0.00 (-0.06, 0.02)) was significantly greater than the control group (P<0.01) and correlated with lower limb functional performance. Conclusion Although patients after ACL reconstruction have no significant difference in balance function compared to normal individuals, their subjective questionnaire scores are still poor. Moreover, the bilateral lower extremity differences in the Y-balance test are highly correlated with lower extremity function, suggesting the asymmetry of bilateral lower extremity balance function.