Abstract: The present invention provides a microbicide which comprises a phosphate represented by the following general formula:M.sub.a.sup.1 A.sub.b M.sub.c.sup.2 (PO.sub.4).sub.d.nH.sub.2 Owherein M.sup.1 represents at least one element selected from the group consisting of silver, copper, zinc, tin, mercury, lead, iron, cobalt, nickel, manganese, arsenic, antimony, bismuth, barium, cadmium and chromium, M.sup.2 represents at least one element selected from tetravelent metal elements, A represents at least one ion selected from the group consisting of hydrogen ion, alkali metal ions, alkaline earth metal ions and ammonium ion, n represents a number which satisfies 0.ltoreq.n.ltoreq.6, a and b each represents a positive number and satisfy la+mb=1 or la+mb=2, and when a and b satisfy la+mb=1, c is 2 and d is 3, and when a and b satisfy la+mb=2, c is 1 and d is 2, where 1 is valence of M.sup.1 and m is valence of A.