The reduction in chemical fertilizer combined with organic amendments is an effective way of realizing the green and sustainable development of agriculture in China. In this paper, we studied the effects of reduced fertilizer application combined with straw return and biochar on rice yield, nutrient absorption and soil carbon to provide a scientific basis for optimizing nutrient resource management in the region's farmland and the resource utilization of straw. A field plot experiment was carried out for two consecutive years in the lime concretion black soil area. Five treatments were set up, including no fertilizer (CK), conventional application of chemical fertilizer (100%NPK), 20% reduction of chemical fertilizer (80%NPK), 20% reduction of chemical fertilizer plus biochar (80%NPK+S), 20% reduction of chemical fertilizer plus straw returning (80%NPK+B). The rice grain yields, aboveground biomass, the content of N, P and K in grain and straw, soil total organic carbon (TOC) and microbial biomass carbon (MBC) were measured and analyzed. The results showed that biochar and straw returning combined with chemical fertilizer reduction by 20% had shown an effective increase on the grain yield and aboveground biomass of rice, in which the effect of biochar exhibited better effect than that of straw returning. The average yield and aboveground biomass of rice in 80%NPK+B treatment was 5.2% and 4.7% higher than those in 100%NPK, and 7.9% and 7.2% higher than those in 80%NPK, respectively. Compared with 100%NPK treatment, the average yield and aboveground biomass of rice in 80%NPK+B treatment increased by 3.4% and 3.0%, respectively. In terms of nutrient uptake by rice, the addition of biochar combined with chemical fertilizer reduction by 20% improved efficiently the nitrogen, phosphorus and potassium absorption of rice, which were 10.4%、7.2% and 20.0% higher over 100%NPK treatment, respectively. The addition of straw combined with chemical fertilizer reduction by 20% could efficiently improve the nitrogen and potassium absorption of rice, while reduce the phosphorus absorption at the same time. It was also found that the application of biochar or straw combined with chemical fertilizer reduction by 20% promoted the accumulation of soil total organic carbon and significantly enhanced microbial biomass carbon at maturity. The benefit of biochar application was better than that of straw retuning in increasing total organic carbon content, while straw retuning performs better than that of biochar in improving microbial biomass carbon content. In conclusion, biochar application combined with chemical fertilizer reduction by 20% or straw returning combined with nitrogen and potassium fertilizer reduction by 20% has the potential to increase or maintain the same levels of rice yields, enhance nutrient absorption, and benefit the fixation of soil organic carbon and in lime concretion black soil along the Huai River.