Abstract: ZigBee positioning principle was used to set up the safety warning system in the Guan-River Bridge construction project. The positioning algorithm was optimized according to the reality of the bridge construction environment,including optimized placement of reference node,optimization and improvement of the localization algorithm,design of minimum energy and etc. Moving average filter was used to improve the localization algorithm,so that the accuracy and stability of the positioning is increased. Meanwhile,the design of energy consumption for this system was optimized by application of minimum battery consumption routing principles,to lower the energy consumption. This method was successfully used in the Guan-River Bridge's construction site in Jiangsu Province's sea-side high-grade highways project and the level of safety management in the bridge construction was improved.