The Tencteri and Usipetes are an ancient Germanic tribe, or tribes, located on the eastern bank of the lower Rhine in the 1st century BCE.

They are known primarily from Julius Caesar's account of his campaigns against them in his Commentarii de Bello Gallico.Tacitus mentions the Tencteri and Usipetes (Usipi) in his Germania, an ethnographic account of Germanic peoples and customs, and records in his Agricola that a cohort of Usipi, perhaps synonymous with the Usipetes, took part as auxiliaries in the military campaigns of the general Agricola in Britain.

While the Usipetes and Tencteri were referred to by the Romans as Germanic rather than Gallic, their recorded names are most reasonably explained as Celtic: Usipetes translates as "good riders" and Tencteri as "the faithful".