With many of the top-ranked players giving the tournament a miss, world number eight Lee took advantage to upset his sixth-ranked opponent 21-19, 11-21, 21-18 in Sydney.
It was his sixth career win on the BWF World Tour and came on the back of victory at the Thailand Open last month.
Ohori triumphed with a gutsy 17-21, 21-19, 21-16 come-from-behind beating of 35th-ranked Indonesian teenager Ester Nurumi Tri Wardoyo.
It was only her second title on tour, having won her first at the Thailand Masters this year.
In the men's doubles final, China's He Ji Ting and Ren Xiang Yu swept past Indonesian pair Mohammad Ahsan and Hendra Setiawan 21-11, 21-10
But another Indonesian duo, Febriana Dwipuji Kusuma and Amallia Cahaya Pratiwi, broke through to win the women's doubles, having lost previous finals at the Spain Masters and Thailand Open.
They recovered from a game down to oust Malaysia's Lai Pei Jing and Lim Chiew Sien 12-21, 21-7, 21-13.
Chinese top seeds Jiang Zhen Bang and Wei Ya Zin overcame countrymen Guo Xin Wa and Chen Fang Hui in the mixed doubles decider by two-games-to-one.
The circuit moves to Fort Worth in the United States next.
