The invention provides an efficient active bio-organic fertilizer produced by using livestock manure and a preparation method thereof. The preparation method comprises the following steps: pre-treating the livestock manure, straw and peat; mixing the livestock manure, straw and peat at a weight ratio of (3-5):(1-2):(1-2); adding a composite ageing bactericide based on the condition that the weight ratio of the mixture to the high-concentrated organic material ageing bactericide is (5000-10000):(1-2), evenly mixing, and then carrying out composting fermentation for 7-10 days, wherein during the composting fermentation, the material needs to be stirred 1-2 times each day; and mixing the material decayed by fermentation with a functional composite bactericide which is generated by single fermentation at a weight ratio of (5000-1000):(1-2), granulating and drying at low temperature so as to obtain the high-efficiency and active bio-organic fertilizer. The process is relatively simple, is easy to operate, and can be used for lowering the product cost is low, saving energy and turning wastes into wealth, thereby being beneficial to promotion of benign ecological circulation and environment conservation; and by utilizing the fertilizer, the quality of the product is good, thereby obviously improving the yield and quality of agricultural products.