Amanda Redman says the world of showbusiness still has "an archaic way of looking at females" over the age of 50 when it comes to dishing out roles.
The New Tricks star told the Mirror that the absence of women like her on TV, while her male counterparts face no such issue, is strange given the prominence of the demographic among telly audiences.
"You’re not going to relate to a teenager, you’re going to relate to somebody who’s near your age," said the 65-year-old star.
Redman added: "And so it seems to me to be very short-sighted. And it makes my blood boil. It’s so wrong.
Watch: Emma Thompson discusses "double standards" around ageism in Hollywood
"Many of us, many of my contemporaries, feel the same way as I do. I get letters and things from women saying exactly that.
"The under-representation of women of this age really does make women feel like they aren’t important anymore and that, from a mental health perspective, is very damaging."
Redman, who is currently co-directing a Chekhov adaptation at the Edinburgh Festival with friend David Threlfall, said she no longer enjoys birthdays and hates ageing.
She said: "I hate it. Apart from the fact you physically start to change – and not just for vanity reasons, things start to hurt and ache.
"I’m a very energetic person, so that drives me potty. And you start losing people. That’s happened to me."
Redman spoke last month of her struggle to come to terms with the passing of her New Tricks co-star Dennis Waterman.
She said: "He was incredibly kind and incredibly generous. He was a gentleman through and through. And not just a wonderful friend, but also a fantastic colleague as well – to everybody."
Redman's stint as a director at the Fringe comes in the wake of the fourth series of The Good Karma Hospital — in which she plays expat doctor Lydia Fonseca — airing on ITV.
The show's creator, Dan Sefton, has hinted that a fifth series is very much on the cards.
Watch: Sharon Osbourne accuses Simon Cowell of ageism