Portugal opened the scoring through Ronaldo's penalty in the 33rd minute.
Just before half-time, Portugal forward Andre Silva lashed out at Michael Boxall after a tussle with the New Zealand defender, which left him with a torn shirt - but could easily have also resulted in a red card.
Chile face Australia and Germany play Cameroon on Sunday to determine the final standings in Group B.
Mexico came from a goal down to claim a 2-1 win over host nation, Russian Federation in Kazan thanks to a goal in each half by Nestor Araujo and Hirving Lozano.
The destination of the other semi-final ticket seemed anything but a foregone conclusion for a short while, with Russian Federation forging ahead in the 25th minute through Alexander Samedov's precise, low drive.
"We started very well and were probably the stronger of the two teams, we could have potentially have gone 1-0 up".
"We're obviously at a disadvantage", Chile coach Juan Antonio Pizzi said.
The Euro 2016 champions took the lead on 33 minutes through a penalty from their captain, his 75th worldwide goal, before Manchester City-bound midfielder Bernardo Silva knocked in a second from close-range only to pick up an ankle injury which saw him substituted at the break.
Mexico booked a berth in the semifinals with the win, while Russian Federation was eliminated after finishing third in Group A with three points, followed by New Zealand at the bottom with zero.
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With Ronaldo dominating All Whites defenders in the air midway through the first half, the next aerial challenge saw two leave him in a heap with rugby-style physical skills.
Silva scored eight Ligue 1 goals last season as Monaco upset the odds to depose Paris Saint-Germain, who had won the last four French league titles.
Four minutes later, Eliseu was set free down the left by Ricardo Quaresma's clever pass and he pulled the ball back into the middle, where Bernardo Silva turned it into the net, although he suffered a knock on the ankle in the process.
Cristiano Ronaldo now has 75 global goals.
His loudest ovation was for applauding back to the crowd when substituted midway through the second half.
Andre Silva added a third on 80 minutes before Nani completed the rout in stoppage time to ensure Portugal finished above Mexico on goal difference.
New Zealand at least came close through captain Chris Wood but their threat was akin to a water pistol when compared to Portugal's heavy artillery with the All Whites' Stefan Marinovic standing between his team and a real pasting.
Tommy Smith and Michael Boxall were guilty of blocking, but Danilo seemed to hook his foot under Smith's leg and went down very easily in the box.
"Overall though, it was a fair victory", said Portugal coach Fernando Santos.