Application of nitrogen inhibitors is an effective way to improve nitrogen fertilizer use efficiency of rice. The effects of nitrogen inhibitors (urease inhibitor N-butylthiophosphoramide, NBPT and nitrification inhibitor 3,4-dimethylpyrazole phosphate, DMPP) and their combinations on yield, nitrogen efficiency and soil nitrogen were studied by field experiment, aiming to provide scientific basis for formulating scientific nitrogen management and reducing nitrogen loss of paddy field in plain along the Huaihe River. A field experiment (between June 2018 and October 2018) using rice cultivar of "Changnuo" 1 as test materials was conducted in Huaiyuan County, Anhui Province (a typical rice growing area along the Huaihe Plain). Five treatments were set up, which were CK (no nitrogen fertilizer), U (urea only), U+NBPT (urea plus NBPT), U+DMPP (urea plus DMPP) and U+NBPT+DMPP (urea plus combined application of NBPT and DMPP). The results showed that addition of NBPT or DMPP into urea increased the yield, nitrogen absorption and utilization, in which the effect of NBPT was better than that of DMPP, and the combination of NBPT and DMPP showed synergistic effect. Compared with U treatment, the rice yield of U+NBPT, U+DMPP and U+NBPT+DMPP treatments significantly increased by 6.8%, 4.3% and 8.6%, respectively, and plant nitrogen absorption increased by 9.6%, 6.5% and 12.2%, respectively, and the difference between the treatments were significant (P<0.05). Furthermore, the addition of NBPT or NBPT+DMPP in urea both significantly improved the nitrogen recovery efficiency (NRE), nitrogen agronomic efficiency (NAE), nitrogen uptake efficiency (NUP) and nitrogen partial productivity (NPFP) (P<0.05). However, urea combined with DMPP also increased in varying degrees, but the difference did not reach a significant level (P>0.05). In addition, the addition of DMPP or NBPT+DMPP in urea both significantly enhanced soil NH₄⁺-N content and microbial biomass nitrogen (SMBN), while reduced soil NO₃^--N content at maturity, and increased the ratio of NH₄⁺-N to NO₃^--N. However, adding NPBT only had no obvious effect. In summary, adding urease inhibitor NBPT or nitrification inhibitor DMPP into urea could effectively improve rice yield and nitrogen use efficiency in plain along the Huaihe River, and the effect of urea added with combination of NPBT and DMPP was the best.