Harriet Harman has written to major broadcasters asking about the number of older women employed within their organisations, the Labour Party has said.
The move is part of the Commission on Older Women's work on females in the media and public life, which Ms Harman chairs.
The shadow deputy prime minister and shadow culture secretary said there needed to be "more change" especially in relation to "this combination of ageism and sexism" faced by older women.
Speaking on Sky News' Murnaghan programme, she said: "I think that there is a lack of recognition that actually women's value is not just during their reproductive years or just what they look like.
"It's just a bit of an old fashioned attitude and there's a whole new generation of older women who don't fancy the idea that they are written off and regarded as past it because they are past 60. There's quite an angry movement out there, we've got a Commission on Older Women and actually the economy loses out, public life loses out, as well as it being unfair and discriminatory."
She added: "I think that there's a combination of age and sex discrimination which doesn't apply to younger women, although they obviously still struggle with balancing a work and family, doesn't apply to older men."
Addressing host Dermot Murnaghan, she went on: "As you move into your prime, which you have not yet achieved, people will think all your wisdom, all your experience that that is really worth something, but if you're a woman it would be like the clock is ticking away should we be getting somebody younger in."
She told BBC1's The Andrew Marr Show hosted by Jeremy Vine there was a new generation of older women who regarded themselves as being equal to men and were not happy to be told they were 'past it' at over 60.
She said: "I think in public life that's very evident, including in broadcasting where you know and it's very welcome that you see many young women blazing a trail coming forward, but they disappear out of sight as soon as they reach their 50s let alone their 60s. So we don't think that that is acceptable, it wastes a lot of talent and expertise, it's discriminatory and women are not going to put up with it."
It was not right, she said, that women ever felt they were on "borrowed time".