NOVELTY - The bioactive composite material comprises solid magnesium phosphate, and microorganisms homogeneously distributed in the composite material. The composite material is formed by solidification of aqueous solutions or dispersions of magnesium salts and/or magnesium oxide with water-soluble phosphate salts of ammonium-, alkali- or alkaline earth metal ions and/or with ammonium phosphate in presence of dispersed microorganisms, and/or aqueous dispersions of sintered products made of magnesium phosphates and/or magnesium oxide with ammonium phosphates in the presence of dispersed microorganisms.    USE - Bioactive composite material useful as a biocatalyst for the material conversion or as a biofilter for the purification of polluted wastewater, where the composite material is present as bioactive shaped body, granules or coating on a substrate (all claimed).    ADVANTAGE - The bioactive composite material can be efficiently and economically produced with less effort, improved abrasion resistance, high mechanical, thermal and photochemical stability and high transparency.    DETAILED DESCRIPTION - The bioactive composite material comprises solid magnesium phosphate, and microorganisms homogeneously distributed in the composite material. The composite material is formed by solidification of aqueous solutions or dispersions of magnesium salts and/or magnesium oxide with water-soluble phosphate salts of ammonium-, alkali- or alkaline earth metal ions and/or with ammonium phosphate in the presence of dispersed microorganisms, aqueous dispersions of sintered products made of magnesium phosphates and/or magnesium oxide with ammonium phosphates in the presence of dispersed microorganisms, aqueous solutions or dispersions of magnesium compounds and other alkaline earth compounds with ammonium phosphates in the presence of dispersed microorganisms, and/or aqueous solutions or dispersions of magnesium compounds with water-soluble phosphate salts of ammonium-, alkali- or alkaline earth metal ions in the presence of dissolved or dispersed polymers and dispersed microorganisms. The dispersed polymer is cellulose product such as bacterial cellulose or microcellulose. The portion of the polymers contains 1-30 wt.% of additives related to the dry biocomposite. The microorganisms are living bacteria, dead bacteria, yeasts, fungi, spores of bacteria or fungi, or micro-algae, where nutrients such as carbohydrates, proteins, vitamins and spline are added for ensuring the viability of living organisms or cells and polyol compounds such as glycerol, sorbitol, trehalose, cellulose and/or other compatible solutes are added for increasing the bioactivity. The microorganisms are 0.1- 50 wt.% related to the dry biocomposite.