The invention discloses a high-pressure washer, and belongs to the technical field of washing equipment. The high-pressure washer comprises a cabinet. A piston cavity, an air storage cavity and a material storage cavity are formed in the cabinet. The air storage cavity is positioned below the material storage cavity. The piston cavity is positioned on one side of the air storage cavity and communicated with the same through a single-way valve. A manual piston is slidably mounted in the piston cavity. The air storage cavity and the material storage cavity are both connected to a handheld pneumatic nebulizer. An air inlet of the handheld pneumatic nebulizer is communicated with the air storage cavity through an air pipe. A feed port of the handheld pneumatic nebulizer is connected with the material storage cavity through a rubber pipe. By the high-pressure washer, the problems that conventional high-pressure washers have poor effect in extracting viscous liquid and are greatly influenced by power sources are solved; the high-pressure washer is widely applied to manufacture of high-pressure washers.