Dumeril's monitor (Varanus dumerilii) is a lizard species belonging to the Varanidae family and is native to Southeast Asia. It is predominantly dark brown in color as adults, often with faint, irregular yellow crossbars along its back.

Juvenile Dumeril's monitors have shiny orange-red or yellow heads, a coloration that fades within 4–8 weeks. Adults can grow up to 4.5 feet (1.4 meters) in total length, although they typically measure around 4 feet (1.2 meters).

This species is found in southern Burma, northern Thailand (north of the Isthmus of Kra to Kanchanaburi Province), Peninsular Malaysia, Singapore, and across various islands including Borneo, Sumatra, Riau, and Bangka–Belitung in Indonesia.

Dumeril's monitors prefer dense evergreen forests with high humidity and also inhabit mangrove swamps, ranging from sea level to elevations of 900 meters (3,000 feet).

Known as specialists in consuming crabs, V. dumerilii also feeds on snails, other molluscs, insects, fish, frogs, turtle eggs, birds, and smaller rodents. Despite its wide distribution, much remains to be discovered about this species compared to other monitor lizards.