Functional microorganisms in bio-organic fertilizer are the core of bio-organic fertilizer efficiency. The manufacturing process of bio-organic fertilizer determines the number and application effect of functional microorganisms. Trichoderma viride has both growth promoting and biological control functions and has been widely used in the preparation of bio-organic fertilizer. Trichoderma viridis was inoculated into compost materials with different maturity（GI value of 50%， 80% and 100%）by dilution inoculation method and secondary fermentation method respectively to prepare bio-organic fertilizer. Pot experiment was conducted to study the colonization ability of the two types of bio-organic fertilizer in the roots of pepper and its control effect on pepper blight. The results showed that 24 days after application of bioorganic fertilizer，when the bioorganic fertilizer was produced by secondary fermentation（the bioorganic fertilizer produced by secondary fermentation after inoculation with Trichoderma viridis when the GI value of compost material was 50%，80% and 100%，respectively） in the root colonization amount of Trichoderma viridis in pepper plants was 1.5×10⁵ ，2.3×10⁵ and 1.02×10⁵ CFU/g， respectively. When the bioorganic fertilizer was produced according to dilution inoculation method（bioorganic fertilizer produced by Trichoderma viridis inoculated according to dilution ratio when the GI value of compost material was 50%，80% and 100%，respectively），the colonization amount of Trichoderma viridis was 0.29×10⁵ ，0.72×10⁵ and 0.24×10⁵ CFU/ g，respectively. When the GI value was 80%，the bioorganic fertilizer inoculated with Trichoderma viridis and produced by secondary fermentation showed the strongest colonization ability in the rhizosphere of capsicum. The control effect of bioorganic fertilizer treated with secondary fermentation was significantly higher than that of the bioorganic fertilizer treated with Trichoderma viridis inoculated with dilution ratio，and the bioorganic fertilizer produced with GI value of 80% was the best. The bioorganic fertilizer produced by secondary fermentation after inoculation with Trichoderma viridis was inoculated with 80% GI. The results showed that the proliferation of Trichoderma viridis after 7 days was 3.91 times，showing the best proliferation and colonization effect of functional microorganisms. In conclusion，the best way to prepare Trichoderma viridis bioorganic fertilizer is to inoculum Trichoderma viridis in compost with 80% rot degree for secondary fermentation，which can not only improve the colonization effect of Trichoderma viridis bioorganic fertilizer，but also improve the disease resistance effect.