The fine structure of the eggs of Aedes (Ochlerotatus) theobaldi, Ae. (Och.) sagax and Ae. (Och.) procax is described with reference to scanning electron micrographs. In all three species, the ventral surface of the egg is more curved than the dorsal. Detailed structure is fairly uniform over all surfaces. Outer chorionic cell structure in the three species is basically similar, with each cell containing one or more large tubercles surrounded by several to many small ones positioned around the periphery of the cell. Large tubercles are single or fewer, and also larger in the anterior portion of the egg in Ae. theobaldi and Ae. sagax. Small tubercles are most numerous in Ae. theobaldi; least so in Ae. procax.