Based on the Shanxi Linyi Yellow River Bridge, an experimental study was conducted to investigate the wind-induced vibrations and control measures of an ultra-long steel launching nose during the incremental launching construction of a steel-concrete composite girder bridge. First, the dynamic characteristics of the bridge structure were analyzed using the finite element method. Then, aeroelastic models of the bridge with the launching nose were designed and fabricated. Wind tunnel tests under turbulent flow conditions were carried out to examine the buffeting responses of the launching nose under different yaw angles. Finally, considering the actual characteristics of the bridge, an inclined stay cable system anchored at the center of the pier was proposed to suppress the wind-induced vibrations of the launching nose. The results show that under the design reference wind speed, the standard deviations of vertical and lateral displacements at the cantilever tip of the launching nose are 0.10 m and 0.04 m, respectively. Within a yaw angle of 30°, the vibration responses remain relatively constant, while a significant reduction is observed when the yaw angle exceeds 30°. The proposed inclined wind-resistance cables can reduce the vertical vibration magnitude at the cantilever tip by approximately 50%.