Rietberg (German: [ˈʁiːtˌbɛʁk] ⓘ) is a town in the district of Gütersloh in the state of North Rhine-Westphalia, Germany.

Wenzel Anton, Prince of Kaunitz-Rietberg, the Austrian chancellor, inherited the county from his mother.

In the year 1807 Rietberg became a part of Kingdom of Westphalia, while the title Count Rietberg remains extant in the House of Liechtenstein, with Hans-Adam II, Prince of Liechtenstein and each born member of his dynasty and their dynastic wives bearing the title currently.

The village itself was not independent anymore, in the year 1843 the municipality Rietberg was established.

There are several other interesting historical buildings in the town like the Altes Progymnasium, the chapel of St John or the old Court House.

And there are some traditional Schützenfeste, which are fairs featuring shooting matches in Rietberg.

Now there is an area with parks, gardens and playgrounds in Rietberg that can only be entered after paying an entrance fee.