A method for making controlled-release ammonium phosphate fertilizer has the following acts of: cracking, pulverizing, blending, aging, drying, and adding release-controlling materials into an ammonium phosphate slurry during preparing processes or adding release-controlling materials in achieved ammonium phosphate powder. Selectively, sulfuric acid is added into the mixture of the release-controlling materials and the ammonium phosphate slurry or ammonium phosphate powder to acidify the mixture. In this method, the release-controlling material combines with the ammonium phosphate by chemical bonding to control the release of nitrogen and phosphorus nutrients to enhance the use efficiency and elongate fertilization effect of the controlled-release ammonium phosphate fertilizer. Additionally, manufacturing equipment of the present invention are basically the same with the equipment manufacturing the conventional ammonium phosphate fertilizer and the raw materials such as release-controlling materials are easily obtained for free, no extra manufacturing and product cost increase in the present invention.