The changes of several defense enzyme activities and phenolic compound in cucumber roots were examined after biological soil amendment(BSA) was applied to the cucumber continuous cropping through pot trials.It could promote seedling growth and reduce disease incidence.The results showed that the activities of defense enzymes such as peroxidase(POD),polyphenol oxidase(PPO) and TTC in treated cucumber roots were measured significantly higher than that of control.The activities of POD and PPO in BSA-treated roots were significantly higher than that of control after inoculation with Fusarium oxysporum(Schl.)f.sp.Cucumerinum.Phenolic compound content of roots decreased in the initial period of inoculation,increased after di-sease incidence,but it was higher in BSA-treated than that of control.These indicated that BSA could induce the defense enzyme activities and increased phenolic compound in cucumber roots.