The invention relates to the technical field of mechanical engineering, in particular to a safety winch for a crane, which includes a take-up wheel, a first fixing frame and a swing rod, a motor is provided at the front end of the take-up wheel, and a fixed rear end of the take-up wheel A brake device is connected, and the brake device includes a brake caliper body, a piston, a rubber ring, a friction block, an oil inlet pipe and a brake disc, and a brake caliper body is provided inside the brake device, and the brake caliper body is slidingly connected There is a piston, and the rubber ring is connected outside the piston. In the present invention, through the two brake caliper bodies, one is used as a normal brake and the other is used as an emergency brake. When the normal brake fails, the emergency brake is activated. It can not only ensure that the work efficiency is not affected, but also improve the safety of the working environment. This kind of design concept is novel, scientific in design, has huge economic benefits and broad market prospects, and is worth popularizing and using.