The invention relates to a loader and aims to solve the problem that an existing loader can not automatically brake for preventing collision during reversing. The invention provides an anti-collision protection system for a loader. A coil of a reversing trigger relay is connected with a reversing trigger signal generator in series, and a normally open contact of the reversing trigger relay is sequentially connected with an obstacle detection trigger signal generator and a coil of a brake signal relay in series; a movable contact of the brake signal relay is connected with a manual brake signal generator, a normally closed static contact is connected with an electromagnetic coil of an emergency brake electromagnetic valve, and a normally open static contact is connected with a coil of a power shutoff signal relay in series; the manual brake signal generator, the contact of the power shutoff signal relay, a first way of switch of two-way interlocking switches and the power shutoff signal input end of a shifting manipulating system are sequentially connected in series; and the manual brake signal generator, a second way of switch of the two-way interlocking switches and the electromagnetic coil of the emergency brake electromagnetic valve are sequentially connected in series. The anti-collision protection system provided by the invention can realize automatic or manual emergency brake operation so as to avoid rear collision.