Keila-Joa is a small borough (Estonian: alevik) in Lääne-Harju Parish, Harju County, northern Estonia.

The borough is home to the third most powerful waterfall in Estonia, Keila Falls.

In Keila-Joa there is also a small hydroelectric power plant with a capacity of 365 kW.

The present manor house was built in 1831–1833 and designed by St. Petersburg architect Andrei Stackenschneider.

It was built for the family of count Alexander von Benckendorff (whose graves can be found in the park on the opposite bank of Keila River, in Meremõisa) and the building saw many prominent guests during the Imperial years, among others the Russian royal family, famous soprano Henriette Sontag and composer Alexei Lvov.