Research Park Boulevard (State Route 255 or SR-255) runs from I-565 to Bob Wade Lane on the north and west sides of Huntsville in Madison County, Alabama. Much of the route is a limited access highway, with the entire route planned to be limited access. The road will eventually be extended to create a near-complete bypass around Huntsville.

State Route 255 was created around 1969 as part of a proposed northern bypass of Huntsville. The original route ran from Redstone Arsenal Gate 9 to US-72 as limited access highway with exits for U.S. Highway 72 Alternate/State Route 20 (now I-565), Old Madison Pike, and ending at US-72, with plans to extend north. SR-255 only appeared on maps and was unsigned, and was better known as Rideout Road.

During the construction of I-565 in 1990, a truck towing a crane dislodged the southbound bridge over SR-20 forcing an earlier replacement of the bridge. SR-255 was first signed as an exit off of 565.

SR-255 was extended north in 1996 to State Route 53. In 2001, the road was renamed Research Park Boulevard for Cummings Research Park, which the road bisects.

In 2005, a three mile extension was constructed to connect with Bob Wade Lane on the north side of Huntsville. This section was named in honor of Martin Luther King, Jr. and built to the same road standards as the present at-grade portion of SR-255, allowing for future upgrade to limited access. The road was built as part of a deal with the Toyota Motor Manufacturing Alabama Plant to allow faster access to I-565.

In late 2009 or 2010, work will begin on an interchange at State Route 53, according to the Alabama Department of Transportation.

A $500 million Southern Bypass through Redstone Arsenal, which will extend SR-255 south from its current terminus at 565 to US-231 in south Huntsville, has been proposed. It will become part of the proposed Memphis-Huntsville-Atlanta highway. As of 2009, the project has been put on hold indefinitely due to military security concerns.

In 2010, the city of Huntsville will begin construction to extend SR-255 to US-231/US-431 North towards Meridianville parallel to Bob Wade Lane. Long-range plans call for SR-255 to be built east and south to US-72 east of Huntsville.

The entire route is in Madison County.