The invention relates to a rat-proof device of places such as an enterprise warehouse, electrical equipment and a transformer substation, in particular to a rat-roof device capable of automatically opening a door. The rat-roof device comprises a housing (4) mounted at a doorsill, wherein a protruding cylindrical doorsill (1) is axially mounted in the housing (4) through a bearing (5); a protective plate (3) covers the housing (4); the cylindrical doorsill (1) is driven by a motor (2) positioned outside the housing (4) to rotate; the motor (2) is controlled by a position switch mounted at a handle side of a door frame via a contactor. A colorful pattern layer is arranged on the surface of the cylindrical doorsill (1). The rat-proof device capable of automatically opening the door is reasonable in design, and is used to replace a conventional rat-proof partition plate, so that difficulty of entering and existing the door is effectively reduced, and absence of a rat-proof interval is eliminated.