Cherie Blair said "tokenism is a very negative thing" when asked whether the next Labour leader should be a woman.
Speaking on the Peston show, the wife of former prime minister Tony Blair, said she doesn't think it "matters" whether the next leader is a woman.
"Role models do matter for sure, but tokenism is a very negative thing, so I don't think it matters, one way or the other, whether the next leader of the Labour Party is a man or a woman," Mrs Blair said.
"What does matter is it is the right person for the job and the person who can turn the party outwards rather than inwards."
The barrister set up the Cherie Blair Foundation for Women in 2008 to help women entrepreneurs in developing countries become successful business owners.
But she said when talking about stereotypes, "women are treated differently to men."
Mrs Blair added: "This idea that a woman's place is not at the forefront, that's a man's place and woman who speaks out is therefore unnatural, aggressive."
She was also quizzed on Prince Harry and Meghan's criticism of the British media, and responded: "My husband always said complaining about the British media is like complaining about the British weather, it's not something you can change."
Transport Secretary Grant Shapps also appeared on the show, in the wake of the government's decision to nationalise Northern Rail.
Mr Shapps said he wanted to introduce a railway body, as a successor to Network Rail.
“There will be a national body who will be the organisation who are in control and they will decide how the investment works, working with mayors, regional leadership, and the rest of it," the Transport Secretary said.
"[It will] be a much less fragmented railway… It’s going to take time to do.
"This is a multi-year thing to put in place, but we can start on it, in fact have already started on it straight away.”
Asked if the Northern Rail franchise was now in the public domain for good, said: “No it’s not, but I’m probably just less ideological than other people about these things, I basically came to this job as a frustrated commuter.
"What I want to see is the trains run on time and it’s clear that on Northern and on some other networks this was just not happening. Cancelled, delayed, not running on Sundays, really an appalling service and I’m just not prepared to see that continue.”