Numbers of indoor navigation systems have been proposed by using different sensing technologies. However, there is still lack of research on blind people focused indoor navigation system. This study aims to develop a high accurate indoor navigation system for blind people to meet this demand. The proposed system is based on inertial measurement unit, which is infrastructurefree and robust. The kinematic characteristics of walking have been investigated. The step frequency detection algorithm and the step length estimation method are developed. Moreover, an effective positioning correction algorithm has been proposed to improve locating accuracy. The experiments showed that this indoor navigation system have a high positioning accuracy, and capable to provide navigation service for blind people in indoor environment.