Veteran Labour MP Helen Jones is to stand down ahead of December's election after 22 years in Parliament.
In a resignation letter, the 65-year-old member for Warrington North said it would not be "fair to my constituents, my party or my family" to stay on until she reaches 70.
Ms Jones said she hoped she would be succeeded by a woman.
Graham Friend, chairman of Warrington North Labour Party, said people would be "very sorry to see her go".
Ms Jones has represented the seat since 1997 and served on the party's front bench between 2010 to 2015 while in opposition, including a spell as Shadow Home Office Minister.
'Contempt for women'
She wrote: "I also hope that some people in our party will not try to undermine my successor in the way they have tried to do to me".
Earlier this year, she claimed there was a "culture of contempt for women" in the Labour Party, giving examples of "bullying and harassment" from activists and councillors towards female MPs.
Ms Jones said MPs were being targeted by local party members who wanted to deselect them because of their gender.
Nick Bent, who stood unsuccessfully for Labour in neighbouring Warrington South in 2010 and 2015, said a "fresh start" would be "good news for the town".
Mr Friend said Ms Jones had "lived and breathed Warrington North for more than 22 years, often working seven days a week for the communities she loves".
He added: "She has never shied away from her responsibilities to stand up for what she believes in, and the people she represents.
"The Labour Party will announce our candidate for the general election in the coming days."