- L. C. Angle, Jr., Collection, 1860/20013
- L. Claire Kincannon theatre collection, 1941/201520
- L. Jane Hastings Architectural Papers, 1951/19985
- L. S. Rhodes & Sons Papers, 1886/19231
- L. VanLoan Naisawald papers, 1958/19601
- Labor History Collection of Publications and Artifacts, 1937/19591
- Laborers' International Union of North America, Local 814, Records, 1960/19631
- Ladley Husted papers, 1959/19632
- Ladwig Family Papers, 1870/19592
- Laila W. Pearsall Personal Papers (SC-10)14
- Laine family papers, 1772/19614
- Land Grants, 1749/19851
- Land Records of the MVLA, 1858/20065
- Landmarks Society of Alexandria, Virginia Collection (MS079), 1934/19764
- Lane Carlson papers, 1937/197224