M. G. Ramachandran (1917–1987) was the former Chief Minister of Tamil Nadu.

MGR may also refer to:

• ManaGeR (MGR), graphical window system
• Mere Gook Rule (MGR), controversially claimed Vietnam War engagement policy
• Merry-go-round train, British freight-train design
• Metal Gear Rising: Revengeance, a video game developed by Platinum Games
• Mġarr, Malta, postal code

Mgr. is an honorific or abbreviation for:

• Manager (disambiguation)
• Monseigneur (also Msgr.)
• Monsignor (also Msgr., Mons.)