The Montgomery County Courthouse Historic District, designated in 1986, includes several buildings listed on the National Register of Historic Places in Rockville, Maryland. The two-block district is focused on what remains of Rockville's old commercial, governmental, and residential center, most of which was demolished during urban renewal in the 1960s.

The district includes the Romanesque Revival-style Red Brick Courthouse, designed by prominent Baltimore architect Frank E. Davis and built in 1891. Located at 29 Courthouse Square, it houses the refurbished Grand Courtroom of Montgomery County Circuit Court. The district also includes the 1931 Neoclassical-style Grey Courthouse and its 1960s addition; the 1939 Georgian-styled post office of limestone construction; and the 1930 Art Deco stone building built for the Farmers Banking and Trust Company.

The courthouses are part of a cluster of municipal and county buildings at the corner of Maryland Avenue and Jefferson Street (Rte 28) in downtown Rockville. Other buildings in the cluster include Rockville City Hall, the District Court of Maryland for Montgomery County, and the Montgomery County Judicial Center, a Brutalist building constructed in the 1980s at 50 Maryland Avenue, which houses the rest of Montgomery County's Circuit Court, the Offices of the Sheriff, the Register of Wills, the Orphans' Court, and the State's Attorney for Montgomery County.

There have been four courthouses in Rockville since it was established as the county seat in 1776. Court was held at the Hungerford Tavern until a frame courthouse was erected in the 1790s. In 1835, the General Assembly funded a new brick courthouse. In 1890, the legislature approved funding for the Red Brick Courthouse.

From 1927 to 1954, the lower level of the courthouse served as the headquarters of the Montgomery County Police Department.

• Montgomery County Courthouse Historic District, Montgomery County, Inventory No.: M: 26-11, including photo in 1975, at Maryland Historical Trust website