Abstract: Blight disease of Zelkova schneideriana is a disease found firstly in the Z. schneideriana. In order to investige the blight disease of Z.schneideriana and pathogen identification. The occurrence of the blight disease in Zhenjiang area was investigated. The pathogen was determined by Koch's postulates. The species of the pathogen were identified based on morphological and molecular characteristics. The detailed results are listed as follows: The disease occurs in forest and nursery, and leads to the death of trees and saplings. The symptoms include slow chlorosis of leaves and rot of its roots. The pathogen was identified through isolation,inoculation and re-isolation. After further research on morphologic properties and rDNA-ITS sequences, the pathogen was identified as Fusarium oxysporum. This study also indicates that the disease is a soil-borne diseases, and the occurrence of disease is concerned with topography, and severe disease often occurs in low-lying wet areas in the field. The disease is transmitted through surface water. Large quantities of chlamydospores are produced by F. oxysporum. These spores invade the roots. Then root cortex begins to rot, tree begins to wither.