The purpose of this study is to quantitatively evaluate foot motions in the normal and hallux valgus(HV) patients using a proposed multi-segment foot model. Results showed that HV patients exhibited relatively smaller flexion/extension, especially in terminal stance. An early abduction at the ankle during terminal stance was also noted in HV patients, which resulted in an excessive abduction in subtalar joint. In HV patients, medial MP joints exhibited excessive amount of adduction during terminal stance. In HV patients, hallux MP joint and talocrural joint exhibited excessive external rotation over the whole period of gait cycle. Understanding the detailed foot motions by the present multi-segment foot model would be very useful to diagnose and to treat patients with various foot diseases.