We measured the feeding rate of the striped earwig,Labidura riparia(Pallas) on third-instar fall armyworm,Spodoptera frugiperda(J. E. Smith), at three constant temperatures and at three humidities. Striped earwigs ate more larvae at 30°C than at 25 or 35°C. Humidity did not affect feeding rate. Rogers' random predator equation described the effects of prey density on feeding at 30°C and 80% RH. Search rates were ≍1,127 and 4,355 cm2/d, and handling rates were 20 and 22.1 prey per day for males and females, respectively. Females consumed more prey than males. The striped earwig appears to bean excellent biological control agent for arthropod pests in row crops.