The London Eye shut on Wednesday night after a piece of metal fell off and hit a canopy, showering visitors with glass.
The attraction was able to reopen on Thursday morning after engineers worked through the night to make repairs and find out what happened.
Teenagers who were boarding the Eye were hit by some glass, but managers said no-one was injured.
A metal pin cover from the wheel's hub came loose and fell about 70 metres onto protective safety glass.
London Eye spokesman David Sharpe said: "I'm very pleased to say the toughened glass worked very well.
"Having studied the CCTV footage, we did a very good job in evacuating the area because, at the time, we weren't sure what had happened."