Multiple Group One winning jockey Gary Palmer has died unexpectedly, aged 53.

The retired Queensland rider had a new career as a racing steward and worked on the panel at the Gold Coast races on Saturday, just hours before his death.

Racing Queensland's chief steward Alan Reardon said he had been shocked to receive the news.

"I have known Gary for 40 years. He was a champion jockey and had been an integral part of the stewards panel since he joined us," Reardon said.

Palmer was an outstanding apprentice jockey riding close to 400 winners as a junior.

He was 16 when he won his first Group One race on Grey Affair in the 1977 Doomben Cup.

Palmer outrode his allowance and was transferred to Tommy Hughes in Melbourne where he tasted Group One success on Salamander in the 1978 Toorak Handicap.

He returned to Brisbane in the early 1980s and continued to ride winners including Daybreak Lover in the 1986 Stradbroke Handicap.

Palmer had stints in Macau and Hong Kong before returning to Brisbane and winning another Stradbroke in 1995 on Rouslan.

After retiring in the late 1990s he dabbled in business ventures before joining the stewards panel in January 2012.

Palmer's sons Matthew and Michael were both talented apprentice jockeys.

He is survived by his wife Debbie and two sons.

SOME OF GARY PALMER'S BEST WINS:

Stradbroke Handicap (Daybreak Lover 1986, Rouslan 1995), Toorak Handicap (Salamander 1978), Brisbane Cup (Love Bandit), Doomben Cup (Grey Affair 1977), Chipping Norton Stakes (Grey Affair 1978), QTC Oaks (Look Aloft 1984), QTC Derby (Florissa 1977).