The injection tooling with designed optimal conformal cooling channels manufactured by AM technology, can greatly improve production efficiency, make finished products more uniform, and avoid product defects caused by uneven distribution of cooling channels and uneven cooling speeds. When developing new products, the digital development method of AM can reduce development costs, shorten the development cycle, and meet the needs of multiple prototype modifications. When manufacturing complex molds, the production cycle can be greatly accelerated due to the intermediate links of cooling channel processing and splicing are removed.