The invention provides a multi-size and self-adaptation soft-pack cigarette packet forming die box and a soft-pack cigarette packet packaging and forming device. The forming die box comprises a left die ruler, a left die pressing plate, a right die ruler and a right die pressing plate. The left die pressing plate is connected to the left die ruler, and the connecting position of the left die pressing plate and the left die ruler can be adjusted. The right die pressing plate is connected to the right die ruler, and the connecting position of the right die pressing plate and the right die ruler can be adjusted. A forming die cavity of a soft-pack cigarette packet is defined by the left die ruler, the left die pressing plate, the right die ruler and the right die pressing plate. The packaging forming device comprises a push plate base, a cigarette push seat, a cigarette push shaft, a cigarette push block, a die box pressing plate, a positioning block, a cigarette assembling die box, a cigarette guide die box, a cigarette channel guide block, a forming bottom plate and the soft-pack cigarette packet forming die box. By means of the multi-size and self-adaptation soft-pack cigarette packet forming die box and the soft-pack cigarette packet packaging and forming device, the problems that existing equipment with a single structure cannot solve the problem about the packaging and forming requirement of cigarette products of various sizes, various types and different specifications, the beneficial effects that the equipment cost is low, operation is simple and convenient, and the packaging efficiency is high are achieved, and the market popularization prospect is wide.