Hundreds turned out for the early afternoon ceremony to swear in Lieutenant General Sir Jerry Mateparae, who was formerly chief of the New Zealand Defence Force from 2006 and 2011.
He replaces Sir Anand Satyanand, who was honoured at a state farewell at Parliament a fortnight ago.
Sir Jerry is the 20th governor-general and the 10th New Zealander to take on the five-year role, considered by many to be the de facto head of state.
Today's ceremony included a full powhiri from a kapa haka group and the inspection of a 100-strong royal guard of honour of navy, army and air force personnel.
A 21-gun salute, reserved only for heads of state, was fired from Wellington's Point Jerningham by the Defence Force's 16 Field Regiment.
Sir Jerry swore an oath of allegiance and oath of office in the presence of Chief Justice Dame Sian Elias and the Government's executive council, including Prime Minister John Key.
The ceremony comes after a flurry of preparation including the construction of a stage on the steps of Parliament last week and final dress rehearsals yesterday.
The only element left completely to chance was the overcast weather, which had cleared up with a peep of sunshine by the time the ceremony began.
Sir Jerry's duties as the Queen's representative in New Zealand will be both ceremonial and constitutional.
They include bestowing honours on distinguished New Zealanders at investiture ceremonies, and signing off legislation passed by Parliament with the royal assent.
Perks of the job include residence at the newly-refurbished Government House in Wellington and use of the official state car -- the only vehicle in New Zealand to carry a viceregal crown rather than a number plate.
The ceremony will be followed by a parliamentary reception at the Grand Hall and a wreath-laying ceremony at the National War Memorial in Wellington.
The Republic Movement today said the role of the governor-general was increasingly at odds with the aspirations of New Zealanders, who it said should be given the right to choose their head of state.
