- Mountain Saddle Band
- Mountain Smoke
- Mountain Sprout
- Mountain Therapy
- Mouse
- Mouse Brothers
- Mover
- Movin' Melvin Brown
- Mr. Baber's Neighbors
- Mr. Chill
- Mr. Joe
- Mr. Joe
- Mr. & Mrs. Chris Bouchillon
- Mr. Ren
- Mr. Sad Head
- MR SKANLESS
- Mr. Wilson
- Mr. Wilson
- Mr. Z
- Mrs. General Dixon Watson
- Mrs. R.N. Grisham
- Mt. Airy
- Mt. Diablo String Band
- Mt. Pisgah Methodist Church Choir
- Mt .Zion Quartet
- Mudcats
- Muddy Marsh Ramblers
- Muddy River String Band
- MudHog
- Mukupa
- Mulehead
- Muleskinner
- Mullet Kings
- Mullins
- Mullins-Black
- Murdoch & Sparrow
- Murphy Ford
- Murphy Gribble, John Lusk & Albert York
- Murphy Henry
- Murry Kellum
- Music City Sounds
- Muskellunge Bluegrass
- Mustang Creek
- Mustang Sally
- Mustard & Gravy
- My America
- My Brave Love
- My Cousin, The Emperor
- My Graveyard Jaw
- Mychela
- Mylon Hayes
- Myra Mevey
- Myra Pearce
- Myrna Lorrie
- Myrtie Payne
- Myrtis Ukwuachu
- Myrtle Brown
- Myshkin
- Mystic Sister