Abstract: More than half of the straw has been burnt or discarded for years in China, which is not only a waste of organic fertilizer but also pollutes the environment. Meanwhile, heavy use of nitrogen fertilizer has become a serious problem in rice production. The practice of returning straw to fields and of using nitrogen fertilizer has important significance for the utilization of resources to reduce environmental pollution. This study investigated the characteristics of root secretion and its relationship to nutrient absorption and utilization in different straw and nitrogen treatments. A mid-season japonica rice cultivar (Xudao 6) was used as test plant with three nitrogen levels (no nitrogen, normal nitrogen and high nitrogen) and straw treatments. N accumulation at grain filing and N recovery efficiency of NN treatment was significantly higher than that of the other treatments under the same straw conditions. Similar results were also observed in some other tested indexes, including malic, succinic, total organic acid, amino acid and root activity. Under the same nitrogen treatment, N accumulation and utilization under straw returned at grain filing was higher than that in the other treatments. Straw returning improved malic and succinic acid contents of tested rice cultivars, but decreased the citric acid content. Root activity, contents of total organic acid and amino acid were also improved under the straw returning treatment. The contents of total organic acid, malic, succinic and amino acid and root activity were significantly correlated with N accumulation at grain filing and N recovery efficiency. Possible reasons for the differences in fertilizer utilization and root secretion characteristics under different treatments are discussed.