- Medical Society of South Carolina Digital Collections80
- Medical University of South Carolina Board of Trustees Collection, 1824-201277
- Medical University of South Carolina University Bulletins, 1878-2002182
- Medical University of South Carolina Yearbooks26
- Mercantile Agency Reference Book of South Carolina175
- Metchicas and Kehayas Family Letters17
- Micajah Adolphus Clark Journals, 1847-18572
- Middleton Family Art Work, 1803-18671
- Middleton Family Papers, 1736-19291
- Middleton Papers, 1775-181512
- Midlands Memories901
- Midlands Memories
9
- Midlands Memories 3
- Millbrook account, n.d.1
- Millicent E. Brown Papers, 1949 - 200377
- Mills Family of Greenville114
- Minutes of the Annual Conferences of the Baptist, Episcopal, Lutheran, Methodist, and Presbyterian Churches in South Carolina, 1785-1920396
- Miriam DeCosta Seabrook and Herbert U. Seabrook Papers, 1882-19959
- Miscellaneous South Carolina Pamphlets3
- Miscellaneous Textiles3