The invention discloses a formula of soil heavy metal composite pollution improving particles. A pig manure organic fertilizer, biomass charcoal, an extracellular polymer, modified tea leaf residue powder, steel slag, a calcium magnesium phosphate fertilizer, clay powder and nanometer manganese dioxide are mixed according to a certain ratio to prepare the particles. The particles have obvious adsorption and fixation effects on soil heavy metal composite pollution, improve the basic physical and chemical properties of the soil in order to improve the microbial environment of the soil, and can fertilize the soil to promote the growth of crops and efficient utilization of nutrients, so the crop yield is increased, and the crop quality is improved. The particles can also adsorb some organic pollutants, so the particles can be applied to the treatment of water bottom sludge in order to achieve the purpose of purifying water. The particles improve the added values of agricultural wastes, promote the recycling and reduction of the wastes, and is a beneficial part of the ecological industry.