The purpose of this study was to investigate the effects of occipital bone stimulation by cervical stabilizing exercise on the muscle tone, stiffness, ROM, and cervical lordosis in patient with forward head posture( FHP). This study was a case study of a single patient with forward head posture. This study used a ABA' design, A and A' were the baseline phases and B was the intervention phase. The intervention was occipital bone stimulation by cervical stabilization exercise. It was administered once daily for 7 days. The therapist kept hands together, and placed the two index fingers under the subject's occipital bone. The subject performed the chin-in exercise with a maximum isometric contraction for 20 sec.The exercise was implemented by performing the movements 10 times as a set and repeating the set three times. The muscle tone was not significantly changed after intervention. However, the stiffness was decreased and lasted the effect lasted without intervention. The cervical flexion angle was increased, but the cervical extension angle was not significantly changed after the intervention. The left and right lateral flexion angles were increased and the effect lasted without any intervention. However, the left and right rotation angles were significantly changed after the intervention. Cervical lordosis increased not from 37° to 41° after the intervention. These results suggest that occipital bone stimulation by cervical stabilizing exercise had a positive effect on cervical stiffness, flexion and lateral flexion ROM, and lordosis in a patient with forward head posture.