The chameleon is generally an omnivorous animal, although some chameleon species are known to have a more carnivorous diet, and other chameleon species prefer to be vegetarians. A chameleon will generally eat anything though including berries, leaves, fruits, insects, worms, snails and some of the larger chameleon species will also hunt small reptiles.
Lots more interesting information here:
(I didn't know that not all chameleons can change color.)
(And an aside: I find that one of the pleasures of growing older is the occasionally effortless learning of new information.)
Actually, they are neither. Carnivorous is a more accurate description. They eat a variety of insects. But if you have one in captivity, you need to be careful about the insects you get for it, both by size and by what the insects have been fed. Feeding the insects properly can lead to a much healthier Chameleon.