Leptobrachella baluensis is found in high elevation primary forests of Sabah and northeastern Sarawak (900–2200 m). They reach approximately 20 mm in both sexes.

This frog is grey above with dark markings (bordered by light color). The supratympanic fold is black and forms a sharp coloration edge. The flanks bear 1 to 4 black dots. Toe and finger tips are pointed. Foot webbing is absent.

This little frog has a very loud high-pitched buzzing call, loud enough to be heard against the background of the small to medium-sized rocky streams were it lives. Males sit on low vegetation (5–30 cm) when calling at night.

L. baluensis differs from mjobergi in elevational distrubution but also in ecology: baluensis prefers streams with coarser gravel. It is not known where this species deposits its eggs. But tadpoles hatch and hide in the crevices of the gravel bed. We found the tadpoles in streams which water was almost exclusively flowing subterraneously.

The tadpole is typical for a Leptobrachella: it is very slender, has a funnel mouth, and a very long tail. They move in a characteristic undulating fashion. Head and trunk radius of action exceed those of other tadpoles.