Abstract: After the investigation of chestnut varieties the selection of the plus tree and the clonic comparative experiment carried out in Yunnan Province from 1991 to 1992,the superior chestnut strain was determined,a Clonic Scion pluching nursery of 6.96 hm² was established and the characteristics of the plus strain was described.Thus,a great number of improved Clonic Scions have been provided for chestnut production.This has accelerated the utilization of improved varieties,the industrialization and commercialization of chest-nut production in Yunnan Province.