Under new party rules, the leader must get at least 60 per cent of support from caucus or it triggers a contest on which the party's membership and affiliates can vote.
The vote, held at a meeting in Auckland this morning, took about half an hour and Mr Shearer was applauded before emerging to announce the results - saying he was safe until the election in 2014.
He said he did not know the exact result because it was a secret ballot - but he had achieved the 60 per cent threshold required - at least 22 of the MPs.
Mr Shearer will travel to Waitangi tomorrow before turning his attention back to his reshuffle, planned for early this year.
That has been on hold partly while Mr Shearer waits for an Auditor-General's report into Shane Jones' decision when he was a government minister to grant citizenship to Bill Liu.
The confidence vote was part of a full-day caucus meeting at an old church at Corbans Estate in Henderson.
On his way into the caucus, David Cunliffe said it was a secret ballot so he would not discuss how he would vote. Last month he said he would endorse Mr Shearer.
Mr Shearer outflanked Mr Cunliffe in an effective challenge at the party conference last year.
Many other MPs going in also refused to say how they would vote, saying it was a secret ballot.
They included Cunliffe allies Nanaia Mahuta, Louisa Wall, and Charles Chauvel.
However, Moana Mackey, regarded as a supporter of Mr Cunliffe, said she will endorse Mr Shearer.
Other MPs also openly said they would vote for Mr Shearer including Phil Goff, Chris Hipkins and David Clark as well as Mr Jones, who said he hoped the venue of an old church would provide some "divine inspiration."
After this year, the new rules will require the confidence vote to be held soon after each election, rather than in the year preceding an election.
