Sydney jockeys have honoured their fellow riders at a sombre ceremony on Jockey Celebration Day.

The annual event commemorates fallen and injured jockeys and raises awareness and funds for the National Jockeys Trust which supports seriously injured riders and their families.

"We recognise the contribution that jockeys make to this great industry," NJT chairman Paul Innes said at the Randwick ceremony on Saturday as rain pummeled the track.

"The courageous men and women who ride on all sorts of tracks in all sorts of conditions, like a day like today."

Reverend Colin Watts and Brother Dan Stafford of the Australian Racing Christian Chaplaincy said a blessing for the jockeys before the crowd took a minute of silence to remember the hundreds of fallen jockeys.

A wreath was laid beneath the bronze sculpture of rider Hugh Cairns at the Randwick fallen jockeys memorial.

Similar ceremonies were held at all race meetings around Australia, with races in each state named in honour of the event.

The topweight in each race at metropolitan meetings wore NJT colours (orange and white).

At Flemington, champion jockey Damien Oliver said the day was about remembering and embracing injured and fallen riders.

"It helps us to remember the jockeys that have given the ultimate sacrifice and lost their life through their love of the sport and racing," Oliver said in a video for the NJT.

"It also gives us time to reflect on the ones that have been injured and are unable to keep on participating as we are."

A memorial garden to commemorate the 89 riders who have died doing their jobs in South Australia was opened at Morphettville in Adelaide before the first race.

Nationally, 880 jockeys have died from race falls since 1847.

INJURED AUSTRALIAN JOCKEYS

* 880 jockeys have been killed in race falls since 1847

* About 200 jockeys are injured on racetracks each year

* 89 per cent of jockeys will have a fall that requires medical assistance

* 40 per cent of jockeys will have a fall that stops them riding for five weeks

* About five per cent of these falls are career-ending

Source: National Jockeys Trust