The midfielder suffered a hamstring problem during QPR's playoff final victory at the weekend, meaning he will miss the tournament in Brazil.
Croatia midfielder Niko Kranjcar has been ruled out of the World Cup because of a hamstring injury.The 29-year-old suffered the injury during QPR's victory over Derby County in the Championship playoff final Saturday and was substituted after 33 minutes at Wembley.
Kranjcar has been an integral part of his national team in recent years and was preparing for his second World Cup appearance.
However, the Croatian Football Association announced on Monday that the former Tottenham man, who has 81 international caps, will not travel to Brazil following an MRI scan in Zagreb.
"Croatian midfielder Niko Kranjcar will miss the World Cup due to hamstring injury," the federation posted on its official Twitter account.
Croatia will appear in the competition's opening game against host Brazil on June 12.