The electrolysis method for synthesizing hydroxyapatite nanoparticles (NPs) has the advantage of controlling particle size by adjusting potential and current used. This study aims to NPs formation its characteristics. solution contained Na2H2EDTA.2H2O, KH2PO4, CaCl2, with an EDTA/PO43-/Ca2+ concentration 0.2/0.2/0.2 M. electrolytic are 4, 5, 6 volts hours. carbon electrode spacing used is 2 cm....