Abstract: Based on the working condition of the pumping well system, through the study on the production string of the oil well, a mechanical model for studying the vibration characteristics of tubing string has been established. From which the mathematical models like wave equation, natural frequency equation and tubing string vibration displacement equation used to describe the tubing string vibration laws have been educed. This paper also studies the relationship between the exciting frequency that can cause the tubing string to resonate and the natural frequency of the tubing string.