Objective To explore the correlation between sagittal balance and plantar pressure in adolescent idiopathic scoliosis (AIS). Methods Forty patients meeting the criteria of AIS were selected. Plantar pressure test was conducted for each patient after they finished the Xray shooting. The sagittal parameters included lumbar lordosis (LL), thoracic kyphosis (TK), sacral slope (SS), pelvic incidence (PI), pelvic tilt (PT), spine sacral angle (SSA) and C7sagittal vertical axis (C7SVA). The plantar pressure parameters included contact area and pressure percentage of the forefoot and rearfoot. The correlation between sagittal parameters and plantar pressure parameters was analyzed. Results Among the sagittal parameters, LL was correlated with SS, PI, PT, SSA; PI was correlated with SS, PT, SSA; SS was strongly correlated with SSA; C7SVA and SSA had a correlation. On the main curve side, LL was negatively correlated with contact area of the rearfoot and whole foot, and positively correlated with the pressure percentage of the rearfoot and whole foot; there was a negative correlation between TK and pressure percentage of the forefoot. PT was positively correlated with contact area of the forefoot, rearfoot and whole foot. Other sagittal parameters such as SS, PI, SSA and C7SVA had no correlation with plantar pressures. On the opposite side of the main curve, there was no correlation between sagittal parameters and plantar pressures. Conclusions In the AIS, the sagittal balance is closely related to the plantar pressure distribution. In particular, the sagittal parameters LL, TK, and PT are most correlated to the plantar pressure parameters.