Old Reliable may refer to:

• The Old Reliable, a novel by P. G. Wodehouse
• Old Reliable Tape and Picture Company, a gay pornography company
• Old Reliable Theatre Tavern in New York City
• The Cleveland Gazette, a weekly newspaper
• Gordo (monkey), a monkey sent to space
• Louisville and Nashville Railroad
• 9th Infantry Division (United States)
• Quincy Mine, a copper mine in Michigan
• RMS Olympic, an ocean liner
• Redstone Test Stand, at Marshall Space Flight Center
• Tommy Henrich (1913–2009), American baseball player