The effect of natural enemies on survival of southwestern corn borer,Diatraea grandiosella(Dyar), eggs and larvae was measured in Texas High Plains corn using exclusion cages.Orius insidiosus(Say) and spiders were the most abundant predators on corn plants. Predation of corn borer eggs was uncommon and insignificant. Survival of first-generation larvae in whorl stage corn where predators were excluded was significantly greater than survival on plants accessible to predators in two of three years. Survival of second-generation larvae on tassel stage corn was significantly greater during both years on caged plants (excluding predators). However, during the second generation, mortality of first and second instars was replaceable by cannibalism among mature, prediapause larvae. Egg and larval parasites were not observed.