Five automatic berths for the Women's World Cup were available at the tournament with the Kiwis sealing one of those thanks to a guaranteed top four finish.
The result also double qualified the Black Sticks for the FIH Women's World League Final in Auckland from 17-26 November, for which they were already an automatic inclusion as the host nation.
Three other sides will join New Zealand at the World League Final following results later today in Brussels, while the top four finishers at the World League Semifinal in Johannesburg will also book a spot.
The Black Sticks now progress to the semifinals in Brussels where they will meet the winner of the Netherlands vs Spain quarter final on Saturday (NZ time).
Head coach Mark Hager said it was great to accomplish the top priority of World Cup qualification.
"It's fantastic to qualify for the World Cup at the earliest opportunity, that was the number one thing for us to tick off here," he said.
"We were finally able to put away some goals which was pleasing. We continue to create plenty of chances and just need to polish the finishes.
"We're now looking forward to the challenge of either the Dutch or Spain in the semifinals, we will watch that game pretty closely and then get ready to play for a place in the final."
New Zealand opened the scoring in the sixth minute when a nice pass across the face of goal found Samantha Harrison open for a straightforward tap in.
Samantha Charlton doubled the lead early in the second half when she received the ball at the top of the circle and sent a rocketing shot past the goalkeeper on her reverse stick.
The Kiwis continued to create opportunities on attack but Italy's desperate defence was able to scramble and avoid any further goals.
Italy put together some good plays of their own in the final 10 minutes but goalkeeper Sally Rutherford made several brilliant saves to keep a clean sheet.
