The WATC Derby, also known as the Western Australia Derby is a Perth Racing Group 2 Thoroughbred horse race for three-year-olds, at set weights, over a distance of 2400 metres at Ascot Racecourse in Perth, Western Australia in April.

[2] The filly, Harridan started as the even money favourite and won by 2 lengths.

[2] The race continued to be part of the WATC Summer Carnival until 1988 when it was moved to April.

The club reverted to the summer schedule in 1993 but by 2002 the race was again being held in April.

[38] The race was once again moved from the traditional summer Christmas/New Year's Day Carnival forward to the autumn of 2002.