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ZA (ammonium sulfate) and NPK (nitrogen-phosphorus-potassium compound) are nitrogen-rich fertilizers commonly used by farmers. The fertilizers have high solubility in water, decay rapidly in wet soil and decompose into ammonia. Its lead into eutrophication phenomena and its absorption by crop roots becomes less effective. A facile and scalable method is developed to hybrid fish scale based powdered hydroxyapatite with nitrogen-rich compounds for slow-release fertilizer. Hydroxyapatite (HAp) is a material that contains phosphorus and is a well-binding agent of nitrogen. This study is aiming at synthesizing HAp from calcium-rich fish scale biowaste using wet-chemical precipitation method and coated the HAp particles with ZA and NPK fertilizer. From the experiment, the total nitrogen content of ZA is 26,95% and NPK is 16,46%. The hybrid ratio is 6:1, and nitrogen release is tested every 120 seconds using percolation method. The percolate contents analyzed using Kjehdahl methods. The nitrogen release of the hybrids is compared to obtain the best kinetics model i.e. zero order kinetics, 1st order kinetics, Higuchi model and Kosmeyer-Peppas models and to analyze sorption isotherm by using BET (Brunauer-Emmett-Teller) method. The use of hydroxyapatite-based slow release fertilizer, might prevent the water resources from fertilizer contamination as well as enhance the crop production using more efficient crop irrigation.