Harnai (Pashto: هرناۍ ولسوالۍ, Urdu: ضلع ہرنائی) is a district in the northeastern part of the Balochistan province of Pakistan.

Harnai is the principal town of this district and serves as its administrative headquarters.

The majority of the population of Harnai are Tareens and they mostly speak a unique dialect, or language, Tarino (Wanetsi), which is quite different from the Pushto spoken in other parts of Baluchistan and NWFP provinces, and is probably a mixture of Pushto, Urdu and other languages developed as a 'lingua franca' sometime during the 18th and 19th centuries, when a variety of people of different ethnic origins lived here.

The summer is extreme in the area and the minimum and maximum temperature fall between 20˚C to 48˚C.

Harnai is one of the most beautiful cities of the Balochistan Province with plenty of water available in the streams.