Chō Chāi Nī — in Lanna language.

Lan Na (Northern Thai: ᩋᩣᨱᩣ; Thai: ล้านนา), also known as Kam Mueang (ᨣᩴᩤᨾᩮᩬᩥᨦ, กำเมือง) or Northern Thai language (ภาษาไทยถิ่นเหนือ), is the language of the Northern Thai people of Lanna, Thailand. It is a Southwestern Tai language that is closely related to Lao. Kam Mueang has approximately six million speakers, most of whom live in the native Northern Thailand, with a smaller community of Lanna speakers in northwestern Laos.

Speakers of this language generally refer to themselves as Khon Mueang (ᨤᩫ᩠ᨶᨾᩮᩬᩥᨦ, คนเมือง), Lanna, or Northern Thai. The language is also sometimes referred to as Phayap (พายัพ), i.e. northwestern speech.

The language may be written in the old Lan Na script, which somewhat resembles that of the Thai, but differs significantly in spelling rules. Due to the influence of the latter, it also differs significantly from the modern pronunciation of Kham Mueang.