The invention relates to a method for measuring high-speed rail bridge vertical dynamic deflection. The method includes: determining a to-be-measured high-speed rail bridge, and arranging a measuringpoint and two reference points on the high-speed rail bridge; controlling a drone with a camera to fly to a set position close to the left side or right side of the to-be-measured high-speed rail bridge, and using the camera on the drone to shoot the to-be-measured high-speed rail bridge at the set position, wherein the left reference point, the middle measuring point and the right reference pointof the to-be-measured high-speed rail bridge can be shot at the set position; calculating the vertical-direction relative displacement of the middle measuring point, the left reference point and theright reference point in a world coordinate system according to the images shot by the camera so as to obtain the high-speed rail bridge vertical dynamic deflection. By the measuring method, environment vibration influence is avoided, flexible and easy-to-operate high-speed rail bridge vertical dynamic deflection measuring can be achieved, and a simple and efficient measuring process is achieved.