No. 36-ranked Pliskova squandered a 5-1 lead in the match after she twice broke the top-seeded German in the first set before losing the next six games.
Lisicki fired five aces in the second set and twice broke her Czech opponent's serve, in the fourth and eight games, to clinch the final in just under 90 minutes.
Lisicki won her last WTA title in Dallas in 2011. It was also her third victory against Pliskova this year after victories at Wimbledon and at the Madrid Open.
The 31st-ranked German had lost three straight finals, including the 2013 Wimbledon final, before her title triumph today.
"After being in three finals last year and losing them closely, this is a big step forward for me," Lisicki told WTATennis.com. "I've won titles in doubles but obviously the main goal is to play well in singles and get these trophies. And I'm even happier because coming here was such a spontaneous decision — we literally decided three or four days before the tournament — and I felt very well in Hong Kong."