The fur is soft, dense, and moderately long. The upper parts may be grayish with a tinge of brownish or yellowish brown, bright reddish brown, glossy brownish black or black, or mottled or blotched across the hips and tail. The upper and lower surfaces of the tail usually have about the same color as the back. The underparts are whitish, grayish, or yellowish. The ears are large and bluntly pointed, the claws are short and blunt, and the flattened tail tapers slightly at the tip.
Females have six mammae.
These flying squirrels inhabit various kinds of forest, as well as clearings and cultivated areas, from about 150 to 3,500 meters in elevation. They are generally arboreal and nocturnal. They shelter in hollow trees, though natives report that they also may take possession of nests abandoned by Ratufa. On Java H. lepidus sometimes nests in a coconut shell in which other squirrels have gnawed a hole. Sometimes the dried shell remains attached to its stem, or the nest is in a loose shell suspended in the crown of the palm tree.