A forming method for a cooling system of a rapid heating mold comprises: preparing a solid cooling waterway object (30) of a default cooling waterway, the solid cooling waterway object (30) comprising multiple interconnected attachment portions (31) and multiple subbranch portions (32); placing the solid cooling waterway object (30) into a container (40) provided with a perfusion groove (41), and the attaching the attachment portions (31) onto a groove bottom surface (411) of the perfusion groove (41); preparing a perfusion material, and perfusing the perfusion material into the perfusion groove (41) of the container (40) to form a mold fixing layer (50) of the solid cooling waterway object (30) after cooling; and taking out the mold fixing layer (50), heating the mold fixing layer (50), enabling the solid cooling waterway object (30) to be in a gas state or a liquid state, and discharging the object in the gas state or the liquid state, so as to form a cooling waterway (52) corresponding to the solid cooling waterway object (30). Accordingly, a cooling waterway in any form can be formed on the mold upon needs, and the effects that the cooling waterway is easy to treat and the heat dissipation temperature of the mold is uniform are achieved.