The 59-year-old British adventurer ran the races in seven continents alongside his running partner Dr Michael Stroud.
After finishing the final run in New York, USA, Sir Ranulph said he wanted hot chocolate and chicken masala.
The money raised will go to a heart charity - the adventurer has had a heart attack and surgery himself.
'Good fun'
"It's the best thing possible," Sir Ranulph said at the finishing line. "It was good fun. We thought it would be and it was."
The biggest challenge was the Singapore race which was run in tropical heat and humidity.
Sir Ranulph described that experience as "hell on Earth". Dr Stroud walked much of the way after suffering a stomach upset.
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