Martin Morris has a collection of 36,000 Marvel and DC comics built up over decades.
The 63-year-old, from Newcastle-under-Lyme, Staffordshire, started his collection when he was aged just five.
His most valuable comic, a 1962 edition that introduced Spider-Man for the first time, is thought to be worth £10,000.
Mr Morris has decided to sell them on eBay after having a heart attack and plans to spend the money on travelling the world.