Smith has said he will not seek re-election as an MP at the next general election.
Owen Smith was “better best forgotten!”
The 49-year-old, who was first elected in May 2010 and spent more than three years as shadow Welsh secretary, was one of a handful of MPs who voted against Prime Minister Boris Johnson’s bid to hold an election in December.
The Pontypridd MP said he was standing down for “personal and political reasons”.
In a letter to Jeremy Corbyn, Mr Smith said it had been a “great honour” to serve the south Wales constituency.
Mr Corbyn had previously sacked Mr Smith from the Labour frontbench after he criticised his position on Brexit.
The Welsh Labour MP made a failed bid to topple Jeremy Corbyn as Labour leader in 2016.
Mr Corbyn made him shadow Northern Ireland secretary but sacked him from that role in March last year, after Mr Smith called for Labour to back another EU referendum.
After that bill was overwhelmingly voted through on Tuesday Mr Smith wrote to Labour leader Jeremy Corbyn saying:
“I write to inform you that, for political and personal reasons, I will not be standing at the forthcoming general election,” he wrote.
“It has been an enormous privilege to serve as a Labour MP and I am truly proud to have represented my home town of Pontypridd over the last decade.”
He added: “I would also like all of my constituents to know that it has been a great honour for me to serve as their member of Parliament.”
Mr Smith posted the letter on Twitter
For political and personal reasons, I have written tonight to @jeremycorbyn informing him of my decision not to stand at the coming General Election. It has been a great honour and a privilege to serve the people of the Pontypridd Constituency. pic.twitter.com/mIxz8spZte
— Owen Smith (@OwenSmith_MP) 29 October 2019
Following the vote in the House of Commons backing going to the country before Christmas Mr Corbyn said: “This election is a once-in-a-generation chance to transform our country and take on the vested interests holding people back.”
Mr Smith is one of seven incumbent Welsh MPs to announce they will not contest the next election.
Aberconwy MP Guto Bebb (Independent), Monmouthshire MP Glyn Davies (Conservative), and Clwyd West’s David Jones (Conservative), along with Labour trio Ann Clwyd, Ian Lucas, and Albert Owen, had all already said they will not stand for re-selection at the next election.