The solitary and secretive little slaty flycatcher spends much of its time hidden amongst dense foliage, and its presence is only detected by its characteristic call (2). It searches in low vegetation in the forest for small invertebrates to eat, and only emerges onto an exposed perch when excited or agitated (2).
Information is scarce regarding breeding in this species, but little slaty flycatchers were found in a breeding condition in May and June (2). Only one nest has ever been found; a frail structure, made of roots and lined with leaves, well concealed in forest litter near the ground. Within this nest were two eggs (2) (5).