The invention discloses a safe escape device of a stair channel. The safe escape device comprises a corridor slide rail and a skid escape compartment, wherein the corridor slide rail comprises a winding operating rail or a reciprocating operating rail; the skid escape compartment is of a closed compartment structure, a fireproof heat insulating plate is arranged on the outer part of a compartmentbody of the skid escape compartment, and a suspending skid frame is arranged on the top of the compartment body; a suspending roller is arranged on the top of the suspending skid frame, and rolls andoperates on the corridor slide rail; two-way top-pushing rods are arranged at left and right sides of the skid escape compartment; a skid controller is arranged inside the skid escape compartment; andthe skid controller comprises a roller gate plate, a gate plate spring and a decelerating pedestal. According to the embodiment, the safe escape device is matched with the stair channel of a high-rise building for use, so that the skid escape compartment has a fireproof and smoke-isolating function, and therefore, even dense smoke is emitted by raging fire in the stair channel, escape staff alsocan be carried to slide downwards. The safe escape device of the stair channel is reasonable in structure and is convenient to control.