The 31-year-old Australian finished at 22-under 262. Robert Karlsson of Sweden was second after a final-round 64.
Raphael Jacqueline was third on 270, while five players were tied for fourth, another stroke back.
Strange, whose previous best result was a second-place finish in the Johnnie Walker Classic in India in March, felt dizzy at one point on the back nine of Saturdays third round.
I was still dodgy this morning, but as the day went on I felt better and better, he said. I knew I had to play decent golf to have a chance to win because I knew the guys would be coming after me.
He was in trouble on the par-5 18th after a poor drive, but managed to save par.
I felt numb on the last tee, he said. I had a vacant brain. I wasnt thinking about the shot to hit, I just felt all I had to do was swing the club.