Abstract: Effects of different winter-green manure on occurrence of diseases, insect pests and weeds of after-reap early rice and its yield were tested to provide technical support for the screening of planting mode in rice planting area of the south. Taking fallow field treatment as control by planting potato, rape and milk vetch as green manure into winter fallow fields, a field experiment was carried out to investigate occurring characteristics of diseases, insect pests and weeds of early rice and its yield change after the winter-green manure plowed. Results showed that different plowed winter-green manure had no effect on occurring species of diseases, insect pests and weeds of early rice, and the main pests were sheath blight (Rhizoctonia solani), stem borer (Chilo suppressalis), rice leaf roller (Cnaphalocrocis medinalis), sheathed monochoria (Monochoria vaginalis) and barnyardgrass (Echinochloa crusgalli), while there was significant effect on the occurring degree of sheath blight, sheathed monochoria and barnyardgrass, and no effect on the occurring number of stem borer and rice leaf roller. Plant morbidity of sheath blight revealed potato-rice > rape-rice > milk vetch-rice > fallow-rice treatment in booting stage, and fallow-rice > potato-rice > rape-rice > milk vetch-rice treatment in yellow ripeness stage. The density of sheathed monochoria and total weeds revealed allow-rice > milk vetch-rice > potato-rice > rape-rice treatment, while that of barnyardgrass was allow-rice > rape-rice > potato-rice > milk vetch-rice treatment. Winter-green manure had no significant effect on rice effective panicle number, grain number per spike and filled grain rate, but it could significantly increase 1000-grain weight and improve rice yield. Selecting appropriate pesticides could effectively control the occurrence of diseases, insect pests and weeds of early paddy rice in early stage of pest occurrence after winter-green manure plowed, and increase rice yield. This study suggested that winter-green manure could inhibit the occurrence of sheath blight and weeds, and increase rice yield in red soil region of Jiangxi, and milk vetch would be the best green manure resource for considering comprehensive effect of improving rice yield and pest control.