In this study, the synthesize of hydroxyapatite-chitosan composites has carried out using the microwave-assisted method. The hydroxyapatite-chitosan composite is interesting to develop based on the application in many fields. Porous hydroxyapatite is very useful for reconstructing damaged bones because it will stimulate the growth of new bone cells. The synthesize of hydroxyapatite utilized waste of Geloina coaxans shells as the calcium source both phosphate sources are ammonium dihydrogen phosphate NH4H2PO4 and KH2PO4 while for synthesis hydroxyapatite-chitosan composites will be carried out using the waste of Scylla olivacea shell as a source of chitosan. The rapid pathway synthesis is very crucial for producing composites. Synthesis has done using the microwave 450 W with a retention time of 20 minutes. Based on the results, the hydroxyapatite powder can be produced with specific peaks of hydroxyapatite at 31.7°. Mass of chitosan influenced pore of the hydroxyapatite-chitosan composite increased the pore diameter of hydroxyapatite-chitosan composite 0.28 to 5.0308 nm and 4.3182 and 7.0268 using KH2PO4 and NH4H2PO4. The functional group also shows the specific bands of hydroxyapatite.