Tetramorium simillimum is a small pale colored ant. This species has a monomorphic worker caste with 12-segmented antennae, three-segmented antennal club, antennal scrobes, short antennal scapes that do not surpass the posterior margin of the head, a gradually sloped mesosoma, and small propodeal spines. Like all myrmicines, T. simillimum has two waist segments and a gaster armed with a stinger. Tetramorium simillimum is believed to be native to Africa and is now widely distributed across tropical regions. The species can achieve dense populations in disturbed habitats and is likely to adversely affect native biodiversity.