Na Noi (Thai: นาน้อย, pronounced [nāː nɔ́ːj]) is a district (amphoe) in Nan province, northern Thailand.

Na Noi was originally named Wiang Si Sa Ket (เวียงศรีษะเกษ).

Erosion formed the strange shapes named Hom Chom, found not far north of the town Na Noi.

The eastern part of the district is in the Luang Prabang Range mountain area of the Thai highlands.

[2] The slogan of the district is "City of earth pillars, area of sweet tamarind, legendary Doi Phachu, praise the chedi Phra That Phlu Chae".