The High Wycombe-based golfer only took up the game five years ago after quitting smoking.
Her victory at Carramar Golf Course over the WA Day long weekend marked the first time she had won a major WA Golf League event.
Donovan, who plays off a 22 handicap, beat more than 140 opponents from 15 clubs across the two-day Stableford competition.
With a score of 36 on day one and 38 on day two, Donovan’s score of 74 edged her past Hugh Fraser (17 handicap) on a count-back, with the Carramar golfer also finishing on 74.
Fellow Carramar golfers Andrew Pyc (73) and Frank Dickenson (73) came third on count-back and fourth respectively.
The competition raised more than $1300 for the Make A Wish Foundation.