Sawitri, Ariani2022-03-142022-03-142021-08wahyu sari yenihttps://repository.unri.ac.id/handle/123456789/10449Composites are two or more materials that macroscopically become a useful material. The purpose of this study was to synthesize hydroxyapatite-chitosan (HAp-C) composite using microwave irradiation heating method with NaH2PO4 precursor and adsorption test on methylene blue. The results of the analysis of the hydroxyapatite mineral phase showed the highest peak at 2ϴ= 33.989°, the functional group analysis showed the hydroxyapatite absorption band in the presence of OH-, PO4 3- and CO3 2- groups. Based on the results of adsorption of Methylene blue using a hydroxyapatitechitosan composite, the optimum conditions for the mass variation of 10% K-HAp-C adsorbent were 50 minutes, 30 ppm, and 5 grams with % Methylene blue adsorbed at 48.32%.encompositehydroxyapatite-chitosanmethylene blueArticle