Nawagai Tehsil (Pashto: تحصیل ناوګای)is an administrative subdivision (tehsil) of Bajaur District in Khyber Pakhtunkhwa Province, Pakistan. Nawagai is the fourth largest of Bajaur District's seven tehsils.

Nawagai Tehsil, the fourth largest in Bajaur District, is 216 km in area and encompasses a valley and parallel ravine separated by a mountain range extending from the border with Afghanistan. Representing Bajaur District's left shoulder, Nawagai shares a 3.14 km border with Bar Chamarkand Tehsil to the west, a 13.58 km border with Mohmand District's Safi Tehsil to the southwest, 1.58 km border with Mohmand District's Pandiali Tehsil to the south, a 13.28 km border with Khar to the southeast, a 13.06 km border with Mamund Tehsil to the northeast, a 2.48 km border with Afghanistan's Marawara District, Kunar Province to the north, and a 4.38 km border with Afghanistan's Sirkanay District, Kunar Province to the northwest.

As of the 2017 Pakistani national census, Nawagai Tehsil has a population of 78,494 people, representing a +1.67% population increase from its 1998 census population of 57,264 compared to a +3.23% population growth in the overall Bajaur District. Residents of Nawagai comprise 7.19% of the Bajaur District population as of 2017.

The vast majority of Nawagai residents expectedly speak Pashto as their mother tongue, the predominant language of ethnic Pakhtuns (Pashtuns) and of the derivatively-named Khyber Pakhtunkhwa Province (KPK). As of 2017, 99.35% of Nawagai residents recorded Pashto as their mother tongue with other residents recording Urdu (268), Brahui (100), Sindhi (35), Kashmiri (33), Punjabi (29), Saraiki (23), and 11 'others' as mother tongues.

As of 2017, 99.98% of Nawagai Tehsil residents reported belonging to the Islamic faith along with 15 Ahmadi and 2 Christians.

Nawagai Tehsil is politically represented in the National Assembly of Pakistan (the lower house of the national parliament) in the NA-8 Bajaur constituency and in the Provincial Assembly of Khyber Pakhtunkhwa in the PK-22 Bajaur-IV constituency. In both bodies, Nawagai Tehsil (as well as Bajaur District and most of KPK) historically elects candidates from the Pakistan Tehreek-e-Insaf (PTI) party established by Pakistani cricketer and 22nd Prime Minister, Imran Khan, who is seen as a fierce advocate for the nation's Pakhtuns, many of whom feel disenfranchised by Islamabad.

• Mamund Tehsil
• Khar Bajaur Tehsil
• Salarzai Tehsil
• Utman Khel Tehsil
• Barang Tehsil
• Bar Charmer Kand Tehsil
• Bajaur District
• Khyber Pakhtunkhwa Province

34°40′02″N 71°17′37″E / 34.66724°N 71.29373°E / 34.66724; 71.29373