- Gaius Dickinson Letters, 1791/19301
- Galt Papers (I), 1745/189216
- Galt Papers (III), 1750/199119
- Gamble Papers, Letters and Photographs, 1774/18861
- Garrett Family Papers, 1786/19281
- Garth Family papers, 1798/18726
- Gary Weiner, Collector, Papers, 1773/19381
- Gaspard Monge Portrait Print, 1746/18181
- Geddy-Harris Archive Records, 1773/1959, bulk 1890/19404
- Genealogy Collection, 1880/20011
- Geo. Gregory Smart collection of Washington and Mount Vernon ephemera, 1793/20175
- George A. Baxter Family papers, 1797/19189
- George Baker Family Genealogy, 1793/19521
- George Couchman Family Papers, 1765/19351
- George Frederick Holmes Papers, 1790/1898, bulk 1842/18871