The invention provides an active collision protector, and belongs to the field of vehicles. The active collision protector comprises a cab floor, a limiting plate and a jacking device; the cab floor is provided with a notch; the limiting plate is rotationally connected to the cab floor and located at the notch; the jacking device jacks up the limiting plate when being stressed by preset collisionforce; the limiting plate rotates relative to the cab floor to a preset angle, by which feet of a driver can be prevented from moving forwards, and is kept at the position of the preset angle. The active collision protector has an obvious protection effect on lower legs of the driver during high-speed frontal collision.