4 January 2016 Last updated at 16:15 GMT
Forty-three per cent of Labour's MPs are female, but the party leader, deputy leader, chair and London mayoral candidates are all male.
Harriet Harman was speaking to former Labour adviser Ayesha Hazarika as part of a report for BBC Newsnight.
Jeremy Corbyn is believed to have started talks with shadow cabinet members as part of a reshuffle.
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Labour's former acting leader Harriet Harman has called for a change in the party's rules to prevent another all-male team from leading the party.