Tetramorium smaug is a species of myrmicine ant native to Ambatovy, Amber Mountain National Park, and Ivohibe in Madagascar.

It was found in montane rainforests around elevations of 900–1,300 metres (3,000–4,300 ft).

It is believed to live in vegetation as opposed to on the forest floor.

The head and mesosoma have rough surfaces while the gaster is smooth.

The species has long propodeal spines with a broad base.