In this study, trans-stadial transmission of the insect growth regulator novaluron, registered in pome fruits in the US, was evaluated on the codling moth. Three different exposure methods, contact, residual and ingestion, were used to determine sub-lethal effects of the compound on adult moths. The result of the study showed that the fecundity of codling moth adults was not significantly affected by novaluron in any of the tested exposure methods. However, the novaluron treatment caused significant reduction in the proportion of eggs hatch in all methods. Contact exposure of novaluron appeared to be more effective than other two methods employed in the study. In the second series of experiments, the effective period of novaluron in or on the moths was tested over an 18 d period for each exposure method. In the contact exposure method the effects of novaluron (i.e. decreased egg hatch) became apparent sooner than other two methods, but its effectiveness was relatively short. Percentage egg hatch in residual and ingestion exposure methods declined from 39.2 ± 3.12 percent and 24.2 ± 3.83 percent to 12.3 ± 3.6 percent and 0.0 ± 0.0 percent as time was extended respectively. From the data we conclude that novaluron was transmitted from parents to offsprings and the exposure method of moths affects this compound effectiveness and effective periods. The sub-lethal effects documented in these experiments represent an important mode of activity contributing to the overall pest efficacy of this compound.