Mashco Piro is an Arawakan language spoken in Peru, by the Mashco Piro or Nomole (meaning 'brothers' or 'countrymen' in Mashco Piro and Yine). It is also called Cujareño. It is very similar to the Piro (Yine), with an estimated 60% inherent intelligibility. Kaufman considered it a dialect of Piro; Aikhenvald suggests it may rather be a dialect of Iñapari. According to the Yine, the language of the Mashco Piro is more archaic than modern Yine, and is about 80% comprehensible with it.

Language documentation is limited, since the Nomole are highly nomadic hunter-gatherers who avoid contact with outsiders. The name Cujareño has been associated with the Panoan languages, though without much evidence.