The basic principle of the sensor is introduced, the composition of connected pipe opto-electronic deflection measurement system is discussed,and it is practically applied in the deflection monitoring of Dafoshi Yangtze River Bridge, The results show that,the data from opto-electronic deflection measurement system can effectively acquire the bridge deflection, and the system is working sound and effectively, measuring range is large than 400 mm and accuracy is better than 0. 1 ram.