A clinical study was conducted in 72 lumbar disc herniation (LDH) patients and 40 asymptomatic subjects to evaluate the efficacy of Feng's spinal manipulation (FSM). FSM was performed twice a week for less than 20 days. Changes in the symmetrical index of spinal column (SISC) and quantified symptom index (QSI) before and after FSM in both groups were collected. The QSI consisted of the visual analogue scale (VAS), score of the Japanese Orthopedic Association, and straight leg raising test, for measurement of pain perception, dysfunction of lower limb extension or flexion, and symptomatic relief. A correlation analysis was conducted to compare the difference in protruded nucleus pulposus size using computerized projection grating profilometry, SISC, and QSI before and after the therapy. The results showed that the SISC and QSI significantly decreased after treatment in the LDH group (p < 0.01). The SISC before and after treatment was closely correlated with the improvement of QSI, although there was no change in protruded nucleus pulposus following the therapy. Among the five components in SISC, the LR was found to be an ideal indicator for evaluation of the real circumstances in LDH patients. Our data suggested that FSM achieved satisfactory therapeutic effects in relieving the symptom of LDH while no effects were observed in asymptomatic subjects.