Abstract As various forces rendering the business environment more dynamic, for survive and prosper, organizations nowadays must rapidly correspond to changes. In order to lower labor cost and develop competition advantage, enterprises always apply human resource flexibility strategy to achieve purposes. However, the practices of human resource flexibility strategy change the job related characteristic, and cause the effect on the psychological contract of employee. And then, it will be the factor for the attitude and behavior of employee in the enterprise. The current human resource arrangement should be adjusted in order to respond to the changes in the market in a timely manner. It is available to implement task flexibility, numerical flexibility, working-time flexibility, and wage flexibility to meet the practical work demands. Our object was domestic bank enterprises, we adopted questionnaire to discuss ¡§the perception of the practices of human resource flexibility strategy¡¨ and ¡§the condition of the psychological contract¡¨ by employees. And then, we explore the relationship between ¡§the perception of the practices of human resource flexibility strategy¡¨ and ¡§organizational commitment¡¨ of employee by the intermediary variable ¡§the violation of psychological contract¡¨. Our results of the research are as the following: There are some practices of human resource flexibility strategy in the bank enterprises, and the employees really have experienced the violation of psychological contract. Finally, through the relation of social exchange, the consequences of Psychological contract will response on Organizational commitment.