The invention discloses a preparation method of an efficient purification composite biological filler, which is characterized in that the efficient purification composite biological filler comprises a filter layer filler, a deep purification layer filler and a gravel layer filler which are sequentially arranged from top to bottom; the filter layer filler is composed of
quartz sand, carborundum and diatomite biological ceramsite, and zero-valent iron,
activated carbon, a compound
microbial agent and a porous slow-release
biomass carbon source are added into the deep purification layer filler. According to the invention,
nitrification and
denitrification are realized in the same reactor, ideal
reaction conditions are provided for biochemical reaction, physical adsorption and biochemical reaction processes are synergistically enhanced, efficient
pollutant removal and water purification effects are achieved, especially, the removal effect on pollutants such as
nitrogen and
phosphorus is obvious, and the method is suitable for industrial production. The device has the advantages of high efficiency, integration, high durability and the like, and can be widely applied to
water treatment facilities such as constructed wetlands, ecological filters,
water treatment biological unit modules, rainwater gardens, ecological oxidation ponds and the like.