Objective To analyze the symmetry characteristics of gait dynamics, kinematics, and spatial and temporal parameters in children with mild leg length discrepancy (LLD) and evaluate the likely influence or risk of LLD on children’s growth to provide a theoretical basis for early assessment and intervention. Methods Using a modified conventional three-dimensional model, 31 markers were placed on the body surface of each subject to collect the gait parameters and calculate the symmetry index (SI). The spatial distance of the ipsilateral markers between the anterior superior iliac spine-external knee-external ankle in the standing position was recorded as the leg length. Then, 59 children with leg length difference in the range of 0.5 cm