Physical up front and clinical at every sniff of the try-line, the three-time champions made a mockery of the idea that a new-look Italy side might scupper their campaign with a first win in 16 meetings between the sides.
crumhalf Aaron Smith scored a hat-trick in the first half and number eight Ardie Savea was a tireless force with ball in hand, securing the bonus point with his first try in the 22nd minute and adding his team's seventh before the break.
Largely absent was the ill-discipline that blighted their warm-up loss to South Africa and first two matches in France, the 27-13 defeat at the hands of the hosts in the tournament opener and an 11-try romp over Namibia.
"We wanted to come out and make a statement. We wanted to dominate up front. Our forwards had the platform and the backs finished it off," said Savea.
"We have talent across the board. We had not really clicked but tonight we played some free rugby and that's how I want my boys to play. Really proud tonight."
New Zealand moved into second place in Pool A with 10 points, ahead of the Azzurri on points difference and three points behind group leaders France, who take on Italy next Friday, a day after the All Blacks face Uruguay.Will Jordan opened the scoring in the sixth minute with a brilliant finish from Jordie Barrett's pinpoint crosskick and his fellow winger Mark Talea also crossed in the first half after a scything break from Savea in midfield.
Despite being 49-3 down, Italy came out with renewed purpose in the second half and livewire winger Ange Capuozzo went over in the corner in the 48th minute for their first try against the All Blacks since 2016.
Sam Whitelock came on in the 50th minute to play his 149th test, surpassing Richie McCaw as the most-capped All Black of all time, and within seconds his longtime locking partner Brodie Retallick barrelled over the line for New Zealand's eighth try.
Flanker Dalton Papali'i scored the ninth, replacement hooker Dane Coles crossed twice and Damian McKenzie came off the bench to make his presence felt by scoring a try and making a second for Jordan.
Replacement centre Anton Leinart-Brown scored the 14th try as New Zealand closed on the 101 points they scored against Italy at the 1999 World Cup.
McKenzie also took over kicking duties from Richie Mou'nga, who had converted nine of New Zealand's first 10 tries, and slotted four conversions from four attempts.
Italy showed great pride in the closing seconds, running the ball from their own tryline to have the final word in the contest through a try from winger Monty Ioane.
"They just monstered us. It was like a training run for them," said Italy coach Kieran Crowley, a former All Black.
"As soon as we got the ball we either gave it away or gave a penalty away. But that was the pressure they were putting on us. We might not even review it, we might just chuck it in the bin."