Abstract: In view of the sensitivity of streamlined main girder to wind load, Xiangshangang Bridge with typical streamlined box girder section was taken as the research object, and performed wind tunnel test on a sectional model. The variations of average drag coefficient, average lift coefficient and average moment coefficient with Reynolds number were studied for the construction and completion conditions of bridge girder section. At the same time, the influence of different railings height on the variation of three-component force coefficient of main girder was analyzed. The result shows that the average life coefficient and the average moment coefficient of the bridge at construction condition increase with the increase of wind attack angle; The variation of the three-component coefficients of the bridge in the vortex vibration range (Re=2.92×10⁴-4.05×10⁴) is complicated; with the increase of Reynolds number, the average lift coefficient and the average moment coefficient basically show a trend that the greater the height of the railings, the greater the coefficient.