Alginate/silica composite beads of mm-size for biomedical applications were prepared from water glass and sodium alginate via a simple sol-gel route. They kept their original shapes when soaked in the phosphate solution of lower pH. In this case, faint calcium phosphate peaks were observed in X-ray diffraction. Peaks corresponding to phosphate group were also found in FT-IR. Apatite was obtained on the surface of beads made with calcium chloride after soaking in phosphate solution while monetite was formed on the surface of beads made with calcium nitrate.