【Objective】Exploring the mechanism of microplastic pollution on N2O emission from agricultural soils at different temperatures. 【Method】In our study, we collected agricultural soils in South China for indoor culture experiments, and selected five different treatments set under three temperature gradients (10°C, 20°C and 30°C), two microplastic concentrations (0.1% and 0.5% mass percent) and two microplastic diameters (74 μm Nlp and 25 μm Nsp) to conduct indoor culture experiments to determine the N2O concentration as well as soil microbial functional Genes. 【Result】Elevated temperature significantly increased soil N2O emissions from agricultural soils (P < 0.001), and the cumulative soil N2O emissions at 30°C were 43.3 and 6.3 times higher than those at 10°C and 20°C, respectively. In addition, elevated temperature increased soil NO– 3 content and decreased NH+ 4 content, and the abundance of AOB, Comammox, nirS, nirK, and nosZ functional genes was the highest at 20℃ and the lowest at 30℃. The effects of microplastic additions of different particle sizes on soil N2O emissions and related nitrogen cycle functional genes varied widely. Compared with the CK treatment, the Nlp treatment significantly increased soil N2O emission by 37.5% and 838.7% at 10°C and 20°C (P＜0.001). Nsp treatment significantly decreased the abundance of Comammox and nirK functional genes and significantly increased the abundance of nirS functional genes in soil (P＜0.001). The results of correlation analysis and random forest analysis showed that soil N2O emission was significantly and positively correlated with temperature and NO– 3, and significantly and negatively correlated with AOA, nirK, nirS, and nosZ (P＜0.05), and that the nosZ functional genes and temperature were the main factors affecting soil N2O emission.【Conclusion】Elevated temperatures significantly increased N2O emissions from agricultural soils, and different particle sizes and concentrations of microplastics had different effects on soil N2O emissions, and there was an interaction effect between microplastics and temperature. The results of this study can provide a scientific basis for investigating the mechanism of microplastic emissions of N2O from agricultural soils under climate change conditions and for risk assessment.