According to the annual abservation results in 1990-1996 on man-made bare slope in Kongshan mountain ous area of south Jiangsu province,the process and affecting factors of natural recovery of vegetation are analysed. The natural recovery process of vegetation began in 1991 (the year after the formation of mam -made bare slope).In 1996,the natural recovery process of vegetation was finished and soil erosion stopped.It is put forward that the prevention of soil erosion on man-made bare slope can not be realised only by the natural recovery process of vegetation.It is necessory to take other countermeasures to prevent soil erosion.