Red-fronted brown lemurs live in multimale-multifemale groups without a noticeable hierarchy, generally numbering from eight to ten individuals, although group size may range between 4 and 18 (2) (5). In western forests aggregations of between 30 and 100 individuals have even been reported feeding in a single fig tree. Breeding is seasonal with infants generally born in September or October after a gestation period of approximately 120 days. A single offspring is usual, although twins have been reported (2). Brown lemurs reach sexual maturity between two and three years, and the lifespan in the wild is believed to range between 20 and 25 years (2) (5).
This species is cathemeral, meaning it is active at varying times throughout the day and night. Fruit, mature leaves, flowers, bark, sap, soil, insects, centipedes and millipedes form the bulk of this lemur's diet (2) (6).