The invention discloses a heating device for low-speed cookoff of insensitive explosives. The problems of partial heating, complicated assembly, low in usage safety, unstable heating power and uneven heating in the testing process in the prior art are solved. The heating device for low-speed cookoff of the insensitive explosive consists of a protection layer, a heating layer, a power connection column, an insulating sleeve, a heat insulating layer and an insulating layer, whole heating is adopted in the testing process, no obvious heat dissipation area exists at two ends, the testing assembly process is simple, the adopted heating layer, the adopted insulating layer, the adopted heat insulating layer and the adopted protection layer are made of a flexible material, safety is high, electric heating pieces are evenly distributed, heating powers at all positions are consistent, the electric heating pieces are embedded into a base material, whole heating is performed through the base material, and the temperature differences of points are small. The heating device for low-speed cookoff of the insensitive explosive can be used for field low-speed cookoff of the insensitive explosives and can be also used for field low-speed cookoff tests of various small-sized live ammunitions.