Kaeng Khoi is a district (amphoe) located in the Saraburi province of central Thailand. It is situated on the bank of the Pa Sak River and is surrounded by the hills of the Dong Phaya Yen Mountains.
The main town of Kaeng Khoi developed during the 19th century, initially serving as a river trading post and a passageway into the Northeast. At the end of the century, it became a railway town following the construction of the Northeastern Railway through the area. In modern times, the district has evolved into a significant industrial center, primarily known for cement manufacturing.