Diamondback moth (DBM), Plutelia xylostella (L), is the most destructive pest of crucifers In Taiwan. DBM larvae feed on crucfferous foliage which reduces the quality and quantity of the produce. Because of the Indiscriminate use of insecticides to combat this pest, the DBM has developed resistance to practically all insecticides used in Taiwan. Efforts were, therefore, made to Introduce parasites to control this pest. The utility of two larval parasftes; Diadegma eucerophaga Horstmann (introduced from Indonesia) and Apanteles plutellae Kurdjumov (collected localty), was investicated in the laboratory, greenhouse, and limited field trials before these parasites were introduced on farmers' fields in Taiwan. none