The effectiveness of tebufenozide applied against the adult, egg,and larvae of codling moth, Cydia pomonella (L.), wasevaluated. Significant reductions in fecundity and egg hatch occurredafter 1-h and 24-h exposures of females and 24-h exposures ofmales-only to residues in plastic plates. A significant reduction inegg hatch was also found after a 1-h exposure of males. The ovicidaleffects of tebufenozide in field trials did not significantly differfor eggs laid on residues or treated topically. Corrected egg mortalityexceeded 95% for cohorts laid <130 degree-days after sprays wereapplied. Fecundity and egg hatch were measured after either a 24-hexposure of moths or a 10-d exposure of moths and eggs on apple trees.Significant reductions in both fecundity and fertility occurredcompared with an untreated control up to 7 d in the 24-h assaysand accounted for 60–70% fewer larvae produced per mated female. Themean numbers of larvae produced per mated female after the 10-dexposure were reduced 100–75% in assays started on day 0–21 afterthe spray application compared with the untreated control. Fecunditywas significantly reduced for 7 d and egg hatch was reduced forthe entire 21-d test period in these trials. Residues had a 14-dhalf-life on apple foliage. Residues applied to foliage or to foliageand fruit did not significantly increase the proportion of uninjuredfruit compared with the untreated control in bioassays where neonateswere placed on foliage 10 cm from fruit. However, the proportion ofinjured fruits with shallow stings versus deep entries was higher onthe treated versus the untreated plants. Field applications oftebufenozide reduced fruit injury >90% when applied early duringemergence. Plots treated after the beginning of egg hatch had a largerproportion of injured fruits with shallow larval feeding.