The world No 14 used his powerful serve to deny the little known 30-year-old from Chinese Taipei in his first ATP final, winning in one hour 41 minutes at the ASB Tennis Arena.
Romantics backing the underdog, who defeated world No 3 David Ferrer in the semi-final, were sorely disappointed but could appreciate the pure class Isner, 28, displayed as he fired 23 aces, some in excess of 230km/h.
What's even more impressive is that the best ones were pulled out when it counted most.
Both players held serve throught the match, although Lu, ranked at 68, had to fight off 10 break points, as the result was decided by tiebreakers. For Isner, who has the world's second best success rate in the tiebreak, it was exactly where he wanted to be.
Landing his first serves at 73 percent, he used American muscle to blast his opponent off the court in the first tiebreaker but was forced to deal with some of the tournament's best winners from Lu in the second.
Up 8-7 and set to serve, Isner fired one final rocket at 229km/h before flinging his arms in the air to celebrate his second Auckland title since 2010 as Lu failed to return.
"This is a fantastic start to the season, just as it was in 2010," Isner said. "I can't ask for a better start. Winning a title doesn't happen all that often - I'm not a guy like Roger [Federer] who has 60 or 70 of them. This feeling never gets old."
Lu can be proud of his efforts at this tournament. In the second set alone he came back from 0-40 to hold his serve twice.
The gusty showing capped off a stunning week during which Lu won his first quarter-final in 11 attempts and caused the biggest upset when he stopped Ferrer's quest for a fourth consecutive title, and fifth overall.
After 13 years on the ATP Tour without a title of his own, Lu said he had thoughts that this might be his last tilt but now feels confident he can produce the breakthrough he has so desperately wanted.
"In the last few years I've played some good matches against good guys but I didn't play so consistently. But this week has really helped me to feel sure that I can play consistently and I can stay until the end of the tournaments," Lu said.
"It's actually good improvement for me so I can get from this week some confidence."
Fans would have been hoping for a final between two of the bigger names in the draw but the spectactle they witnessed was worth every penny spent on entry fees.
Isner showed almost no signs of his troublesome ankle injury and will head to the Australian Open full of confidence where he will play a qualifier in the first round.
In the previous match on centre court, second seeds Julian Knowle and Marcelo Melo defeated the 4th ranked doubles team in the world, Alexander Peya and Bruno Soares 4-6 6-3 10-5 in the final.
It was Knowle's 17th doubles title while Melo now has 13.