John Pugh, MP for Southport, said he planned to retire next month, but "did not bank on the prime minister's opportunism" in calling an election.
He said he did not want to work through "the nightmare chaos of Brexit" in the next parliament.
The local constituency party will now choose a new candidate from an all-woman shortlist.
Mr Pugh said in a statement: "I was going to announce my retirement from Westminster politics in my own time this May after what will be successful local elections."
He said he planned to continue in local politics, but felt it was "the right time to step down and begin a new chapter in my life".
Mr Pugh joins a number of MPs who have ruled out standing in the election on 8 June.
Former Chancellor George Osborne, who is also the editor of the Evening Standard, will not run again to be MP for Tatton.
He announced his plans in the newspaper, adding that he will be "fighting for that Britain I love from the editor's chair".
A number of Labour MPs have also confirmed they will not run following Tuesday's surprise announcement.
On Wednesday morning, both Andrew Smith, MP for Oxford East, and Iain Wright, MP for Hartlepool, confirmed they would not be running for re-election.
One of only nine current Liberal Democrat MPs has chosen to step down ahead of June's general election.