The broadcaster, who presents the BBC's flagship Newsnight programme, said that age should not be a barricade to women working in television and that she intended to stay at her post for years to come.
Wark, who made her name with a tough interview of then-prime minister Margaret Thatcher in 1990, appears on screens 60 times a year.
She said that Tony Hall, the new director general of the BBC, had "laid down the law" on attitudes to older women presenters.
She added: "It's just not acceptable to talk about women going just because of their age. I think that if you try to keep at the top of your game, and if you are still doing good work, then age shouldn't be a barrier. It's not a barrier for men - David Dimbleby's in his 70s."
The comments from Wark, who is also due to front a new culture show, are likely to reignite the debate about female presenters being retired due to age that has dogged the BBC in recent years. Former stars Selina Scott, 62, and Anna Ford, 69, have complained about their treatment by broadcasters, while former Countryfile presenter Miriam O'Reilly won an ageism case against the BBC in 2011.