Karnchang Public Company Limited (CK, Thai: บริษัท ช.การช่าง จำกัด (มหาชน)) is a Thai contractor and construction firm, operating in Thailand and Laos.

Karnchang was founded in 1972 in Bangkok, by Plew Trivisvavet and his four brothers.

Karnchang was awarded the tender to conduct design and civil works for the MRT Orange Line's western extension.

Karnchang's power generation subsidiary, CK Power PCL, constructs and operates a variety of renewable energy projects.

[8] CK Power has constructed dams on the Mekong River in Laos, including the Nam Ngum 2 Hydroelectric Power Plant and the Xayaburi Dam.