Glatt (German pronunciation: [ˈɡlat]) is the name of a lesser affluent to the High Rhine in the Unterland of the canton of Zurich, Switzerland.

Whereas the upper reaches are only gently inclined, the stream gets steeper beneath, forming banks of bed load.

The hydronym reflects the (feminine) OHG adjective glat, meaning either "bright, clear" or "plane, smooth".

In 1936, another straightening was carried out as a preliminary work to the construction of the Zurich Airport as well as to land improvement and future overbuilding.

Due to the last regulation works in 1975 between Niederglatt and the Glatt's confluence to the Rhine, the hydroelectric power stations built in the late 19th century at the lower course of the stream disappeared.