A reformer is someone who works for reform.

Reformer may also refer to:

• Catalytic reformer, in an oil refinery
• Methane reformer, producing hydrogen
• Steam reformer
• Hydrogen reformer, extracting hydrogen
• Methanol reformer, producing hydrogen from methanol
• Kim reformer, producing syngas
• Protestant Reformers
• Reformers Bookshop, Australia
• Reformer (Enneagram), a personality type
• Pilates reformer, an exercise machine
• The Reformers (film), 1916
• Reform movement
• The Reformer, a short-lived American newspaper published in 1837
• Rutherglen Reformer, a Scottish newspaper first published in 1875