The invention discloses a cleaning device for bridge guardrails. The cleaning device for the bridge guardrails comprises a device frame, a lifting and lowering fixing device arranged at one side of the device frame, a cleaning assembly fixed to the fixing device, a wiping assembly and an air-drying assembly, wherein an upper cavity and a lower cavity are arranged inside the device frame; a solar photovoltaic panel is arranged inside the upper cavity; a water collecting tank is arranged inside the lower cavity; a light collecting assembly is arranged on the top of the device frame; moving guidewheels are arranged under the device frame; a water collecting groove is arranged at the periphery of the upper part of the device frame and connected with a rainwater filtering device through a water delivery pipe; and the rainwater filtering device is connected with the water collecting tank. The cleaning device for the bridge guardrails of the invention has the advantages of simple structure,energy saving and environmental protection.