By means of applying indexes of species riehness (S),individual number (N),evenness(E) and Shannon diversity (H),relationship between community structure of big soil animals and harm degree of Oligia Vulgaxis in bamboo forest was studied in Ningguo County. The results Showed that in the bamboo forest seriously harmed by O.vulgaxis the ant nests could be found everywhere and the dominant and common group of big soil animals community and cocoons of O.vulgaxis decreased. The index N was low,while indexes E and H were high.The relationship between the harm degree and indes S was not obvious.In different seriously harmed ecology types,no matter how many indeses S and N were,index H was always higher because of higher index E.