Narrow-mouthed Frogs are specialized predators of small prey, such as ants and termites. Species of Glyphoglossus (formerly Calluella), Kaloula, Gastrophrynoides, and Microhyla are terrestrial or fossorial; whereas others (Chaperina, a few species of Kaloula, Metaphrynella) have the ability to climb vegetation.

Using standing bodies of water for reproduction likely is the ancestral condition for microhylids. Some species, however, have adapted to using small quantities of water accumulating in bamboo internodia, tree holes, Nepenthes pitchers, animal wallows, etc.
The reproductive biology of Narrow-mouthed Frogs commonly includes aquatic eggs and a free-swimming larval stage with highly efficient suspension feeding.

Microhylid tadpoles generally lack expanded oral discs and keratinized mouthparts. The gill spiraculum is situated in postero-median position on the belly.

Some microhylid groups (for example, in New Guinea) have evolved terrestrial clutches and direct development, but this has not been shown conclusively for any of the Borneo species.