Veteran Ryan Archibald opened the scoring after five minutes with a piece of individual brilliance while Shea McAleese slotted in the second at the 16-minute mark.
Nick Wilson made it three just before the break when he tapped in a great cross from Ben Collier.
A second-half revival from Malaysia saw the hosts peg one back to 3-1 but a Shay Neal goal in the 61st minute enabled the Kiwis to comfortably hold on for the win.
McAleese was named man of the match but Collier also impressed with his strong work rate and errorless performance.
In Monday morning's final, the Black Sticks are expected to face either Argentina, who they beat 5-2, or Great Britain, who they went down 2-1 to yesterday.
New Zealand 4 (Ryan Archibald, Shea McAleese, Nick Wilson, Shay Neal) Malaysia 1. HT: 3-0.