The gravity suspension three-dimensional heating device comprises supporting frames which are symmetrically arranged, a first connecting rod and a second connecting rod are arranged on the two sides of each supporting frame in a sliding mode, side heating pieces are arranged on the first connecting rod and the second connecting rod, and the supporting frames are provided with bearing bases which can slide up and down and are used for bearing cookware. The supporting seat is in linkage with the first connecting rod and the second connecting rod through a linkage structure, when the supporting seat supports the cookware, the supporting seat moves downwards and is in linkage with the first connecting rod and the second connecting rod to move inwards, so that the side heating pieces are tightly attached to the cookware, the cookware is placed in the device, the supporting seat moves downwards under the gravity of the cookware, and the cookware is heated to be heated. According to the linkage structure, the first connecting rod and the second connecting rod are driven to be close to the cookware, then the two side heating pieces are driven to be tightly attached to the cookware, bottom heating and side face heating of the cookware can be achieved, efficient heating is achieved, in addition, the linkage structure can guarantee that the side heating pieces are tightly attached to the cookware, heat loss is prevented, and meanwhile the linkage structure can be suitable for cookware of different sizes.