Maryland Route 190, locally known as River Road, is a major state highway through southern Montgomery County, Maryland, United States.

MD 190 begins at MD 112's western terminus in Seneca, and ends at the Montgomery County / Washington, D.C. border. Inside the District of Columbia, River Road continues without designation to Wisconsin Avenue (the District extension of MD 355.

The route is named River Road makes sense–it parallels the Potomac River for most of its course, although the name extends past where MD 190 actually terminates in both directions. MD 190 goes through a few populated areas such as Potomac, Maryland and other suburban areas near DC. It intersects with the Capital Beltway and the Cabin John Parkway about halfway between Potomac Village and DC, at exit 39 on the Beltway. Traffic from Interstate 270 traveling towards Washington is directed to use MD 190 as a preferred route between the outer suburbs and the District.

MD 190 possesses a large number of parks along its route, including the C&O Canal National Historical Park, McKee-Beshers Wildlife Management Area, and Blockhouse Point Conservation Park, among others.

On Tuesday, December 23, 2008, during the morning rush hour, a 66-inch (1,700 mm) water main ruptured along MD 190 near its intersection with Bradley Blvd., causing a major flood along the roadway. Many vehicles were trapped in the water, and a number of individuals had to be rescued by boat or helicopter.

The entire route is in Montgomery County.