The relationship between fecundity and body size in females of the moth Streblote panda Hübner was studied in laboratory by using both virgin and mated females. Strong relationships among fecundity and pupal weight, adult weight, and forewing length were found. The number of eggs in virgin and mated females was similar; mean egg load (number of eggs per female) was 278.4 ± 8.7 (SE), suggesting that S. panda females eclose with all their eggs fully developed. Larger females were more fecund than smaller ones. Mated females laid eggs soon after emergence without any obvious preoviposition period, and no relationship between female body size and age-specific fecundity or female longevity were found. Male size did not show any effects on egg size or hatchability. Data suggest that determinants of larval development such as temperature and food plant may influence fecundity through their effects on pupal weight and adult body size. All studied reproductive traits are characteristic of the capital breeding strategy.