The invention discloses production technology process of a heat dissipation device for an automobile fan. The process adopts a technological mode with the sequence of prefabrication, internal formation and sealing so that the manufacture method of a heat dissipator is greatly changed. A thin board with a regular shape is rapidly formed to be the heat dissipator of a three-dimensional cavity. Therefore, quick formation is realized. The process is simple so that complicated process such as casting and milling are avoided. The cavity with the inside being made of alloy material is manufactured inthe double-layer structure. Therefore, the heat dissipator can have greater heat volume by consuming less aluminum alloy material. Therefore, heat conduction speed of the inside of an automobile is increased. The good performance of the heat dissipator is obtained.