Aliovalent ion substituted hydroxyapatite of formulae BiNaCa3(PO4)(3)OH, Bi0.5M0.5Ca4(PO4)(3)OH (M = K, Ag) were synthesized and characterized. Antimicrobial properties of these synthesized materials were studied quantitatively by spread plate method against the microorganisms Escherichia coli (gram negative bacteria), Staphylococcus aureus (gram positive bacteria) and Candida albicans (yeast). Among the substituted hydroxyapatite compounds bismuth and silver substituted compound of formula Bi0.5Ag0.5Ca4 (PO4)(3)OH shown excellent activity against all the three organisms. Cytotoxicity study was carried out against mouse fibroblast NIH-3T3 cell line in two different concentrations 10 mu g/mL and 20 mu g/mL by MTT assay method. (C) 2014 Elsevier B. V. All rights reserved.