In the study presented in this paper, calculation of the contact patch between a measured wheel tread profile and a designed rail shape carried out strictly by using a general software program called TED/CPA in order to investigate their contact characteristics. A calculation method to obtain the creep coefficient was proposed focusing on a contact patch subject to multi-point contact. This proposed method was then applied to contact conditions between the measured wheel tread profile of a commercial vehicle and the designed rail shape. Results showed that the contact patch shape is composed of many contact areas due to wheel tread unevenness, and the estimated creep coefficient may be smaller than the Kalker's theoretical value.