The invention discloses a preparation method of a mixed manganese cluster molecular-based magnetic material, A magnetic material formed by A manganese clust nano molecular alloy, silver-sulfur nanocluster molecules, iron oxide, manganese oxide and zirconia and, , the non-magnetic material composed of barium titanate, Magnesium oxide, magnesium silicate, apatite and siliceous sandstone are respectively subjected to wet ball milling and freeze drying, and then is added with tetraethylene glycol dimethyl ether, Benzyldichlorosilane, sodium tartrate, calcium benzoate, glyceryl tricarboxylic acid,stabilize reaction and other raw materials, and then respectively through the step of gradient melting, twin screw extrusion, casting mold, rapid cooling of liquid nitrogen, freeze-solidification, nitrogen blow drying, high-temperature steam was, natural air drying and the like to prepare the mixed manganese cluster molecular-based magnetic materials. The mixed manganese clusters molecular-based magnetic materials prepared by this method have excellent electromagnetic properties, high frequency, magnetic flux density saturation, good temperature stability and mechanical impact, and can meet various needs in the industry.