The Lai Tay script (Vietnamese: Chữ Thái Lai Tay), is a writing system used by the Tai Yo people of Quỳ Châu District, to write the Tai Yo language.

[3] Ferlus suggests that the Tai peoples all adopted the same first model of writing borrowed from the Khmers, by simple contact during exchanges, without proper learning.

[2] The script is written vertically from top to bottom and horizontally from right to left on the model of Chinese writing.

This innovation, which is unique in southeast Asia, is very well explained by the influence of Chinese writing; Tai scholars found it more convenient, when translating between Tai and Chinese, to adopt the same writing direction for both scripts.

The script is now being taught and studied by the Tai Yo community, with the support of the local government and teachers.