The invention relates to the technical field of oil injection, and discloses an oil injection device for metro oil pressure dampers. The oil injection device comprises a base, the top of the base is fixedly provided with an oil storage tank, the top of the base is fixedly provided with an oil conveying device located on the front face of the oil storage tank, the left side of the oil storage tankis fixedly provided with an oil inspection pipe, the right side of the oil storage tank is fixedly provided with a mounting plate, the right side of the oil storage tank is fixedly provided with a first connecting block located below the mounting plate, the bottom of the mounting plate is fixedly provided with a hydraulic cylinder, the bottom of the hydraulic cylinder is fixedly provided with a first movable plate located on the right side of the first connecting block, and the top of the base is fixedly provided with a supporting frame located on the right side of the oil storage tank. According to oil injection device for the metro oil pressure dampers, the metro oil pressure dampers of different models and different types can be arranged, so that the applicability is wider, the operation is simple, use by workers is facilitated to the greater extent, oil injection work and assembly work can be performed at the same time, and the working efficiency of the workers is effectively improved.