The invention provides a transformer substation flood prevention device which comprises an electrical cabinet with a power supply, a drainage pump connected with the electrical cabinet through a cable, and a drainage pipeline connected with an outlet of the drainage pump. The transformer substation flood prevention device further comprises a push support provided with traveling wheels at the bottom end. The electrical cabinet and the water drainage pump are both arranged on the push support. The push support is provided with a through hole used for enabling the drainage pump to be placed in a drainage pit. When the transformer substation flood prevention device is used, the push support is pushed to enable the traveling wheels to drive the push support and the electrical cabinet, the drainage pump and the drainage pipeline on the electrical cabinet to travel to the discharge place. Only manual push force needs applying on the push support in the whole conveying process, so that labor intensity of operators is reduced. Meanwhile, the transformer substation flood prevention device can convey all flood prevention tools used for drainage to the discharge place at one time, so that the conveying time of the flood prevention device is shortened, and flood prevention working efficiency is improved.