The R-Class is a multi-purpose vehicle (MPV) offered by Daimler AG in 2006 model year under the Mercedes-Benz brand. It is the first full-sized multi-purpose vehicle ever produced by Mercedes-Benz. It was first seen at the 2001 Detroit Auto Show as the Vision GST (Grand Sports Tourer) concept, and the final production vehicle was shown at the 2005 New York International Auto Show. The R-Class is built on the W251 chassis, and is assembled in Tuscaloosa, Alabama and Toluca, Mexico. It is priced between the M-Class and the GL-Class. It was initially marketed by Mercedes-Benz as a "Sports Cruiser" and later as a "Family Tourer".

The R-Class is offered in two wheelbases, 2,980 mm (117.3 in) and 3,215 mm (126.6 in), the latter being the lone offering in the US.

Models using the BlueTec diesel engine were introduced for the 2009 model year in certain markets, with other markets getting Mercedes' BlueEFFICIENCY technology.

Not all engines are available in all markets.

The R-Class scores "Good" in the Insurance Institute for Highway Safety (IIHS) front crash test. But was given an "Acceptable" rating in the side impact crash test before 2009 models built after September 2008 because the test dummy's torso faced excessive loads. For 2009 models built after September 2008, Mercedes modified the seatbelts and interior door trim and the IIHS rated the R-class "Good" overall in side impacts allowing the R-Class to receive the Top Safety Pick award.