As tadpoles, Hyla regilla feed on plant material. They capture prey by flicking out the tongue, sticking it to an insect, and then bringing it back to the mouth. The tongue is specialized for this because it is coated with a sticky secretion, is relatively long, and is very quick. This procedure is a response to movement, which they detect with sight, smell, and hearing. The problem with this mode of feeding is that they pick up dirt and other debris with the prey, which cannot be sorted out, because they swallow their prey whole.
Males attract females up to a mile or more away with their two toned mating call.
Once females find a male, the two find a temporary pond where they can breed. Eggs are fertilized externally. The male puts his feet on the hips of the female, brings his cloacal aperture close to hers, and releases a cloud of sperm as the female releases her eggs. This egg mass is laid in the temporary pond where it floats, attached to pond vegetation, for about three to four weeks before hatching. It takes longer for the eggs to hatch the colder the water is.