The effects of different organic fertilizers, applied at equivalent nitrogen levels to replace chemical fertilizers on soil microbial communities were studied under equal-nitrogen conditions, to provide a microbiological basis for reducing chemical fertilizer application and offers theoretical guidance for improving soil fertility. Through corn cultivation trials, microbial community structure was analyzed, and the impacts of various fertilization treatments on soil microbial abundance and the correlations between microbes and soil environmental factors were investigated. The results showed that total microbial counts, from high to low, were composted kitchen waste, sheep manure, pig manure, pure chemical fertilizer, and mushroom residue compost. Except for mushroom residue compost, all other organic fertilizer treatments significantly increased total microbial populations compared to pure chemical fertilizer. Therefore, organic fertilizers significantly increased soil microbial biomass and improved soil physicochemical properties more effectively than chemical fertilizers. Bacteria and actinomycetes dominated the microbial communities in corn-growing soils, while fungi played the smallest role. Correlation analysis revealed that bacterial abundance was highly positively correlated with both actinomycete abundance and total microbial count; actinomycete abundance was also strongly positively correlated with total microbial count; fungal abundance was significantly positively correlated with soil moisture content. Bacteria and actinomycetes promoted plant growth except for the pure chemical fertilizer treatment, soil organic matter and total nitrogen in other treatments showed significant positive correlations with corn yield. Therefore, applying composts derived from kitchen waste, sheep manure, or pig manure promotes microbial proliferation, increases corn productivity, improves soil ecological conditions, and supports sustainable agricultural development.