The invention discloses a power assembly protection device of a cold reducing mill. The lower end of a cover is of an open square box-shaped structure, hooks are fixedly arranged on the upper edge of a right side plate and are located on the same horizontal line, a containing table is horizontally arranged on the lower edge of the right side plate, the left end of the containing table is welded to the side plate, protection rods are horizontally arranged at the front end, the right end and the rear end of the containing table respectively, and the lower end of the protection rod is welded to the upper surface of the containing table. The cover is supported by four cover legs, inclined supporting rods are arranged between the front cover leg at the right end of the cover and the containing table and between the rear cover leg at the right end of the cover and the containing table, an external thread is arranged at the lower end of each cover leg, and the cover legs are in threaded connection with an adjusting base. The power assembly protection device has the advantages that the power assembly protection device is simple in structure, sturdy and durable, safe and reliable, multiple different mechanical tools can be placed at a time, workers can conveniently take the tools in the use process and place the tools after use, and meanwhile the power assembly protection device can adapt to the uneven ground in a plant.