Bridge health monitoring system is a new technology applied to bridge management and maintenance in recent years, which has important engineering value. Wireless vibrating wire sensor has the characteristics of strong anti-interference, high precision, long transmission distance, etc., and is widely used in the monitoring of dynamic physical quantities such as vibration and stress in mass concrete structures. This paper mainly discusses the structure of bridge wireless strain monitoring system and the working principle of wireless vibrating wire sensor, designs the vibration excitation circuit and frequency measurement circuit inside the vibrating wire sensor, as well as the wireless communication module, and gives the design of internal software and analyzes the characteristics of the wireless vibrating wire sensor. The wireless design greatly facilitates the use of vibrating string sensor. The practical application shows that the bridge wireless strain monitoring system based on sine sensor designed in this paper is stable, reliable in quality and fast and accurate in measurement data.