The Congressional Cemetery, officially Washington Parish Burial Ground, is a historic and active cemetery located at 1801 E Street in Washington, D.C., United States, in the Hill East neighborhood on the west bank of the Anacostia River. It is the only American "cemetery of national memory" founded before the Civil War. Over 65,000 individuals are buried or memorialized at the cemetery, including many who helped form the nation and Washington, D.C., in the early 19th century.

Christ Church, an Episcopal church, owns the cemetery. The U.S. government has purchased 806 burial plots, which are administered by the Department of Veterans Affairs. Located about a mile and a half (2.4 km) to the southeast of the U.S. Capitol Building, the cemetery is historically associated with the U.S. Congress. The cemetery still sells plots, and is an active burial ground. It is three blocks east of the Potomac Avenue Metro station and two blocks south of the Stadium-Armory Metro station.

Many members of Congress who died while Congress was in session are interred at Congressional Cemetery. Other burials include early landowners and speculators, the builders and architects of early Washington, D.C., Native American diplomats, Washington, D.C. mayors, American Civil War veterans, and 19th century Washington, D.C., families unaffiliated with the federal government.

The cemetery is the resting place of one vice president, one Supreme Court justice, six Cabinet members, nineteen senators, 71 U.S. Representatives, including a former speaker of the House, veterans from every American war, and J. Edgar Hoover, the first FBI director.

The cemetery was listed on the National Register of Historic Places on June 23, 1969, and designated a National Historic Landmark in 2011.

Congressional Cemetery was established by private citizens associated with Christ Church on a 4.5 acres (1.8 ha) plot in 1807, who later gave the property to the church, which gave it its official name Washington Parish Burial Ground. By 1817 sites were set aside for government legislators and officials; this includes cenotaphs for many legislators buried elsewhere. The cenotaphs, designed by Benjamin Latrobe, each have a large square block with recessed panels set on a wider plinth and surmounted by a conical point.

From 1823 to 1876, the U.S. Congress funded the expansion, enhancement, and maintenance of the cemetery, but it never became a federal institution. Appropriations funded a gravel road from the Capitol to the cemetery, paving within the cemetery, the public vault, fencing, and the gatehouse, and funerals for congressmen and the cenotaphs. During the early part of this period, graves were laid out in a grid pattern in an extension of the grid in the L'Enfant Plan for Washington, and little or no landscaping or plantings were made on the grounds. The grid survives to this day and was extended as the cemetery expanded.

Starting in the late 1840s, the cemetery was influenced by the rural cemetery movement in which the graves were placed in a park-like setting with extensive landscaping. To implement this new vision, the cemetery needed to expand.