【Objective】The use of plant growth-promoting microbes to improve plant nutrition and hence reduce the rate of chemical fertilizer is becoming a popular strategy for sustainable agriculture.【Method】In this work, a field-pot experiment, designed to have four treatments, i.e. CF (control, 100% of chemical fertilizer at a conventional rate), Treatment OF (Chemical fertilizer, 75% of the conventional application rate plus organic manure, 50 g·plant^-1), Treatment BF (Chemical fertilizer, 75% of the conventional application rate plus Trichoderma-enriched bio-manure), and Treatment SS (Chemical fertilizer, 75% of the conventional application rate plus Trichoderma spore suspension), was conducted on the crop of tomato.【Result】Results of the field experiment demonstrated that Treatment BF was almost the same in yield as CF, while Treatment OF and Treatment SS was significantly lower than CF. The field experiment and the pot experiment displayed the same trend. In the pot experiment of four successive cropping of tomato, Treatment OF and Treatment SS decreased by 6%~38% and 9%~35%, respectively, in tomato yield as compared with CF. Besides, the treatments significantly affected quality of the tomato fruit (p < 0.05), by reducing NO₃^- accumulation by 32%~46% in the fruit under greenhouse, while Treatments BF and OF increased the content of Vitamin C and the content of total soluble sugar in the fruit by 2%~23% and 35%~54%, respectively. The field experiment also showed that Treatments BF and OF increased the content of total soluble sugar in the fruit by approximately 40% while decreasing NO₃^- accumulation by 42%~57%. In the pot experiment, Treatments BF and OF were significantly higher than CF and Treatment SS in content of available P and K (p < 0.05), while CK was always the highest in content of ammonia-N among the 4 treatments throughout the 4 growing seasons. The soil nitrate-N gradually increased with the cropping going on in all the treatments, particularly Treatments BF and OF, which were significantly higher than CF. Moreover, Treatment BF was much higher than the other two and CF in population of soil microbes and in most cases, it sustained relatively big populations of bacteria, fungi and actinomycetes. Pearson correlation analysis shows that soil nutrients were closely related to population of soil microbes, and that the population of Trichoderma in the soil was positively and significantly related to that of soil fungi and actinomycetes, which may be attributed to the effect of Trichoderma, once colonized in Treatment BF, stimulating propagation of bacteria, fungi and actinomycetes in the rhizosphere of tomato and hence enhancing availability of soil nutrients. The population of soil microbes in the rhizosphere of the crop was also found positively and significantly related to numerous soil fertility indices.【Conclusion】To sum up, all the findings in the experiment suggests that the application of chemical fertilizer, 75% of the conventional application rate, plus Trichoderma-enriched bio-manure can effectively guarantee a stable yield of tomato higher in quality, and in the long run, increase the population of soil microbes and improve soil fertility.