The dynamic processes of soil water movement and interflow occurrence mechanisms for Camellia oleifera ecosystem on red soil sloping land were analyzed based on environmental isotope technologies,soil science and hydrological experiments in terms of morphology and energetics.Results showed that in the initial stage of rainfall infiltration,soil water in the upper layer（0-40cm）was affected obviously by rainfall infiltration and evapotranspiration.The 40-90cm layer was a transitional layer and soil water moved alternately upwards and downwards in rainfall infiltration process.Compared with wild grass ground,Camellia oleifera ecosystem with deep roots was easier for the occurrence of interflow.In the same soil layer,the amount of interflow in Camellia oleifera ecosystem was higher,whereas the peak value of interflow was lower and the progress of interflow occurrence lasted longer.Rainfall on the surface of wild grass ground with shallow roots was mostly lost as surface runoff,so it was difficult for infiltration and storage to occur.With the same vegetation coverage,interflow production,peak,lag and trailing in the upper layer（0-40cm）were less than those in the lower layer（40-110cm）.The dynamic change of stable hydrogen and isotope of soil water indicated that a relatively saturated layer was one of basic conditions for the occurrence of interflow and the interflow was mainly from the displaced initial soil water.