He's damaged a vertabrae in his spine following a fierce challenge by Columbian defender Juan Zuniga.
Zuniga apologised to Neymar after the inicdent-
"I deeply regret the sad injury that Neymar suffered during the match between Brazil and Colombia," he said." Although I feel that these situations are a normal part of the game, there was no intent to injure, malice nor negligence on my part."
And Neymar - super star that he is - sent a message to his fans!
Germany will feel they have a big advantage now with Neymar out of the tournament - but I wouldn't advise them to be too cocky! Brazil, even without their star striker will be very hard to beat.