Ms Hopkin said the couple on average raised $25,000 a year for the event since they participated in its inaugural run six years ago.
She said they had not raised that much this year, but have still managed to generate $15,000 to go towards the cause.
“It will do wonderful things for some very needy children,” she said,
The cruise raises funds for Variety, which is a charity that aims to help WA children who are sick, disadvantaged or have special needs to live, laugh and learn.
The cruise will begin on March 17 at Hillarys and return three days later on Sunday after three days of driving around the South-West, including a stop in Yallingup.
The couple will be doing the cruise in a 1963 Holden EJ Panel Van.
Ms Hopkin said her husband bought the car 12 years ago.
“My husband bought it and restored it from Geraldton,” she said.
“It was a builder’s car up there and now it is being used as a Sunday drive car.”
The couple originally got involved as they had friends involved in Variety and thought the cruise would be the best way to raise money.
In order to gain entry to the cruise, first-time participants must raise at least $3000 while those who have done it before must get to $4000.