The invention belongs to the technical field of soil improvement, and discloses a tea acidified soil remediation bio-organic fertilizer and a preparation method thereof. The tea acidified soil remediation bio-organic fertilizer is prepared from the following components in parts by mass: 20 to 25 parts of biochar, 10 to 15 parts of plant ash, 10 to 15 parts of river sludge, 15 to 20 parts of earthworm powder, 8 to 10 parts of animal waste, 5 to 10 parts of calcium magnesium phosphate fertilizer, 5 to 8 parts of silkworm excrement, 5 to 8 parts of zinc oxide, 5 to 8 parts of montmorillonite, 1 to 3 parts of clay mineral, 1 to 3 parts of rice husk silicon alkali and 1 to 3 parts of bacillus amyloliquefaciens. The organic fertilizer disclosed by the invention can effectively improve the pH of soil and improve the yield and quality of tea leaves; meanwhile, cost is low, raw materials are easy to obtain, the manufacturing method is simple and convenient, and the fertilizer contains rich medium-trace elements and has a soil disinfection function. The soil conditioner can improve the physical and chemical properties of soil, mainly can adjust the pH value of the soil, prevent soil hardening, improve the granular structure of the soil, loosen the soil and increase air and moisture.