- Roger MacBride Allen
- James D. MacDonald
- David Malki
- Sascha Mamczak
- T. L. Mancour
- Andy Mangels
- Phillip Mann
- John Marrs
- Sondra Marshak
- George R.R. Martin
- Michael A. Martin
- Arkady Martine
- Matthew Mather
- Richard Matheson
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- Todd McCaffrey
- Wil McCarthy
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- Vonda N. McIntyre
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- James A. Moore
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- Richard Morgan
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- Peter Morwood
- Sergej Moskwin
- Tamsyn Muir
- Randall Munroe
- Melinda S. Murdock