The invention provides a granular southern paddy field acid soil conditioner using rice husk as a matrix, wherein the raw materials comprise 25-38% of carbonized rice hull, 10-20% of rice hull silicon-alkali, 14-25% of fly ash, 28-40% of silicon-calcium-magnesium-phosphorus-potassium fertilizer, and 2-8% of polyacrylamide. According to the present invention, the conditioner can obviously reduce the bulk density of the soil, can increase the soil porosity and the proportion of large aggregates, can effectively prevent soil from hardening, and can provide a large amount of Ca<2+>, Mg<2+>, K<+> and other salt-based ions so as to perform equal exchange with H<+>, Al<3+> and other acid forming ions adsorbed by soil colloids, wherein the exchanged H<+> and the Al<3+> are neutralized and precipitated with the OH<-> carried by the conditioner and the OH<-> released by the active silicon hydrolysis, such that the problems of acidity and toxicity of paddy field acid soil are fundamentally solved.