The effects of dietary sugar and body size on the oviposition of Ae. aegypti were studied under laboratory conditions. In female mosquitoes provided with sugar, the start of maximum fecundity was significantly delayed and the oviposition period was longer than in females provided with water. The peak of oviposition was also delayed in sugar-fed females. Large females oviposited more eggs per day than small females at maximum fecundity and during eight days of observations. Large females also visited significantly more water-containing cups in their cages per day than small females at maximum fecundity. During the eight days of observations, large females and sugar-fed females visited more watercontaining cups in their cages than water-fed small females. Both large females and sugar-fed females oviposited their eggs at sites higher above the water line than water-fed small females. These results suggested that large and sugar-fed female Ae. aegypti mosquitoes had more energy reserves and oviposited their eggs at higher sites, which would lead to a time lag in hatching.