Foot rot of Moso bamboo (Phyllostachys pubescens) was first found in Jiangsu province in 1975.Now it has been found in provinces of Zhejing,Anhui,Jiangxi,Hunan,Hubei and Sichuan.But it is hetherto unreported from foreign countries.By a large number of isolations,the different pure cultures which belong to four species of Hyphomycetes and a Bacterium were obtained from naturelly infected bamboo stems.Field and greenhouse inoculations were’carried out with above isolates respectively on bamboo shoots.Inoculation results have shown that no infection occurred with Bacterium and only slisht infection with Aureobasidium pullulans or Alternaria alternata,but that severe infection and typal symptom were caused by Arthrinium phaeospermum of Fusarium heterosporum,and reisolations were also secured.Field surveys and isolation experiments have indicated that F. heterosporum never appeared in the initial stage of infection and only in the later period of disease under wet weather conditions, so it is a secondary pathegen.A.phaeospermum is the primary pathogen of this disease.