Abstract: Lecanosticta acicola that is pathogenic fungus of brown spot needle blight could produce pathogenic toxin. Leaded by bioassay,three active fractions(m,p and q) were obtained from metabolites of the pathogen in MS culture liquid by the separation way of combination of silica column chromatography(SCC) and tiny layer chromatography(TLC).Both m and q showed somely blue fluoresent light under 254 nm and 365 nm UV light on TLC plate and had the same Rf values developed by two solvent systems(A and C),which were 0.57 and (0.75) respectively.Active fraction p fraction was yellow-whited fluorescence under (365 nm) and the Rf values were 0.46 and 0.66 developed by A and C,which were different from the Rf values of m and q.These results indicated that two or more toxins would exist in the metabolites of Lecanosticta acicola.