The Portuguese has been at the Bernabeu since the summer of 2009 but hinted following May's Champions League final win over Liverpool that he would be open to an exit.
Italian giants Juventus are thought to have shown an interest, with talk of an £88m offer on the table.
After enjoying so much success in Spain, it is thought Ronaldo is seeking a new challenge but Modric is confident he will not be tempted away from Los Blancos.
'We'll see what happens,' said Modric. 'I don't think he will leave and I'd like for him to stay because he's the world's best player. He means a lot to us and I hope he stays.
'I believe he will stay, that's my opinion. It'd be great if that happened because I can't imagine him playing for another team in Europe.'