A field fertilization experiment was conducted in Jiangxi Red Soil Research Institute in 2015 to study the effects of different organic materials on crop yield and active soil organic components in order to ultimately increase crop yield and soil fertility. Seven fertilization treatments were designed, including no fertilizer(CK), chemical fertilizer (CF), chemical fertilizer reduced by 40%(RF), RF+straw(RFR), RF+biochar(RFB), RF+pig manure(RFP), RF+vermicompost(RFV). Results showed that the treatments of RF+organic materials increased crop yield compared with CF treatment in the sweet potato-rape system, significant higher rapeseed yields were obtained under RFP and RFV compared to CF(P<0.05). The contents of soil microbial biomass organic matter(MBOM), dissolved organic matter (DOM), particulate organic matter(POM) and liable oxidation organic matter(LOM) of RF+organic materials were higher than those of CF, the content of POM in rape season was significantly higher than that in sweet potato season. Correlation analysis indicated that SOM had significant positive correlations with crop yield and active organic components including MBOM, POM and LOM after two seasons of fertilization (P<0.01). Thus, organic materials replacing 40% of chemical fertilizer is feasible in increasing crop yield and enhancing the content of soil active organic components which is very important for soil fertility improvement.