The invention provides a transformer substation transformer oil stain cleaning device which is used for solving the problem that oil stains on transformers are not convenient to clean. A lifting assembly is arranged on the top of a base and provided with a movable plate moving up and down. A big arm is hinged to the movable plate. A big arm oscillating oil cylinder for driving the big arm is arranged on the movable plate. A small arm is hinged to the big arm. A small arm oscillating motor for driving the small arm is arranged on the big arm. A front arm is hinged to the small arm. A front arm oscillating motor for driving the front arm is arranged on the small arm. One end of the front arm is provided with a translational erasing assembly. The translational erasing assembly mainly comprises a translational eraser and a slider-crank mechanism. The slider-crank mechanism drives the translational eraser to do reciprocating movement to conduct erasing operation. A cleaning agent tank is arranged on the base. Nozzles are arranged in the cleaning agent tank. Cleaning agents are sprayed out of the nozzles and sprayed onto translational erased parts. A confluence groove is formed in the cleaning agent tank to collect the cleaning agents. By using the transformer substation transformer oil stain cleaning device, oil stains on transformers can be erased.