Will camilla stay queen when Charles dies?

No, her royal titles are tied to her husband's. If Charles dies, she ceases to be the Princess of Wales (this title will pass to Catherine Middleton). If Charles was to take the throne, Camilla will be Queen Consort only for as long as he has it.

Camilla has stated publicly on her marriage to Prince Charles that she will renounce the official title of Queen in favour of 'Princess Consort'. This was partly in deference to British public opinion which was sharply divided about the future monarch's re-marriage, and the affection which the late Diana, Princess of Wales still retains among the citizens of the UK.

I don't know who has edited my first correction, but that person, whoever they may be, misses a vital point. Camilla is not, as was stated in the original answer, the Princess of Wales. She is not even a princess at the present time, since the Queen has not issued the necessary letters patent according her that rank. She is the Duchess of Cornwall (one of Prince Charles' subsidiary titles is Duke of Cornwall). Upon her husband's accession to the Throne, she will, as my corrector points out become a princess, if that has not been granted her beforehand.

Furthermore, it is likely, though not certain, that the Duchess of Cambridge will be the next Princess of Wales. That title will only be hers if the future King Charles invests Prince William as Prince of Wales, as the Queen did with her eldest son and heir presumptive. I am more than willing to have my responses edited: so long as the editing is carried out with the aim of promoting accuracy, and not muddying the waters.