The availability and quality of nectar for adults are thought to affect fecundity of the cotton bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae). Experiments were conducted to analyze the effect of adult feeding on the fecundity, and oviposition pattern of moths, and larval performance (egg hatch). The moths were fed either on distilled water, honey solution, or one of a range of concentrations of sucrose solution. The results showed that diets with sugars significantly increased fecundity and adult lifespan. Lifespan, total numbers of eggs and egg mass were significantly higher for females that fed on sugar during adult life. Egg hatch (a measure of offspring fitness) decreased over time regardless of sucrose concentration, but had always higher levels in the groups fed sugars. The peak of the ovipositing period was delayed and prolonged, with more eggs deposited, when moths were fed on sugar solution. In conclusion, adult feeding increases the fecundity of female moths and plays an important role in enhancing the fitness of individual cotton bollworm offspring.