To explore the effect of rice-crayfish farming on the stability of soil organic carbon and enzyme activity， a comparative experiment was conducted between rice-crayfish farming model and rice monoculture model using Oryza sativa “Shen Liang You 3117” and Procambarus clarkii as material in 2021 and 2022. The results showed that， compared to the rice monoculture model （RM）， the soil LOC Ⅰ content in the rice-crayfish farming model （RC） increased by 25.85% to 39.13%， the soil MBC content increased by 96.54% to 105.73%， and the soil POC content increased by 92.24% to 132.32% （P<0.05）. Meanwhile， the activity of soil β-XYS in RC decreased by 29.35% to 59.74%， β-GC activity decreased by 17.16% to 53.10%， and ACP activity decreased by 41.64% to 59.12% （P<0.05）. Pearson analysis revealed that soil LOC Ⅰ ， ROC， MBC， and POC were positive correlated with pH， TN， and TOC （P<0.05）， while DOC and C/N ratio were negative correlated with pH and TN （P<0.05）. The rice-crayfish farming model increased the soil pH and TN， reduced the activity of β-XYS and ACP， enhanced the activity of NAG in the soil， and thus increased the content of active organic carbon in the soil.