The mechanical equipment used to apply prestress in bridge engineering is usually called tension equipment. The commonly used tensioning equipment is composed of hydraulic jack and supporting high pressure oil pump, pressure gauge and external oil pipe. Hydraulic jacks can be divided into core jacks and solid jacks according to their structure. The more common tensioning jack on the site is generally a core structure, and its main structure includes a tensioning jacket, a piston and an oil chamber. In order to ensure the quality of the project and construction safety, the jack should carry out factory inspection and type inspection. Taking the YDC3000/58-200 hydraulic jack designed and produced by Liuzhou Overem Machinery Co., Ltd. as an example, this paper mainly studies the type test method of hydraulic jack.