This study investigates whether mother's exposure to the artificial sweetener acesulfame-K (AK) during pregnancy or lactation affected her adult offspring's sweet preference. It was found that mother's dietary exposure to AK in pregnancy or lactation decreased the preference thresholds for AK and sucrose solutions in the adult offspring, whereas the preference pattern and the most preferred concentration for AK or sucrose solution were unchanged. Furthermore, the preference scores in the exposure groups were increased significantly when compared with the control group at a range of concentrations for AK or sucrose solution. The existence of AK and its dynamic changes within 24 h in amniotic fluid during pregnancy or in mother's milk during lactation after a single oral infusion of AK solution were revealed by the methods of reversed-phase high-performance liquid chromatography and mass spectrometry. Our data suggest that AK can be ingested by the prenatal or postnatal mice through their mother's amniotic fluid or breast milk, producing a long-dated function on the adult's sweet preference.