Undoubtedly aided by a leg injury suffered by Monfils early in the first set, Ferrer needed just 49 minutes to dispose of the French former world number seven, five minutes less than he required to win his quarter-final against Lukas Lacko.
The Spaniard, fourth seed for Melbourne Park in the absence of injured compatriot Rafa Nadal, will face Philipp Kohlschreiber in Saturday's final after the German beat American Sam Querrey 6-4 7-6 in the earlier semi-final.
Former U.S. Open champion Juan Martin Del Potro expended similarly little effort in reaching the final of the Kooyong Classic, easing past Marcos Baghdatis 6-4 6-1 at the former Australian Open venue.
The world number seven, who was drawn to play a qualifier in the first round of the year's first grand slam, will meet former world number one Lleyton Hewitt in Saturday's final at the exhibition event.
"I was better than two days ago but I need to improve a lot more," the Argentine said. "It's our first tournament, the season has just started and it's normal to feel strange but with time, tournaments and matches everything is going to be better."
In Sydney, Bernard Tomic overcame dizzy spells and fought off four set points in the opening set before running out a 7-6 6-4 winner over Italy's Andreas Seppi to reach his first ATP Tour final.
The 20-year-old has now gone seven matches unbeaten at the start of the year, including his stunning upset of Novak Djokovic in Perth last week, and is relishing the prospect of running into Roger Federer in the third round in Melbourne next week.
"I've been playing great tennis, and now I'm one match away to win the tournament and my first ever title," he said. "It's going to be a big match. I'm grateful for this opportunity. I think I've got a good shot to win it.
"You know, that third-round meet is huge but the tennis I've been playing now, if I can win tomorrow, it's different approaching the Australian Open."
Tomic's opponent in the final will be South African Kevin Anderson, who clinched his place in the final with a 3-6 6-4 7-6 victory over Julien Benneteau in a gruelling semi-final.
The South African fired down 18 aces to get back into the contest after the Frenchman had won the first set, and wrapped up victory with a volley at the net on his third match point after an exhausting 153 minutes in the Sydney heat.
ATP Auckland results
1-David Ferrer (Spain) beat Gael Monfils (France) 6-1 6-2
2-Philipp Kohlschreiber (Germany) beat 4-Sam Querrey (U.S.) 6-4 7-6(2)
ATP Sydney results
Bernard Tomic (Australia) beat 3-Andreas Seppi (Italy) 7-6(10) 6-4
Kevin Anderson (South Africa) beat Julien Benneteau (France) 3-6 6-4 7-6(8)