Six female protesters from the Animal Rebellion campaign group ran on to the track before the Epsom Derby on Saturday afternoon and were removed by police.
Dozens of police officers could be seen working to remove the protesters, who were wearing sashes reading “Animal Justice”.
The protest came on the 109th anniversary of the suffragette Emily Wilding Davison throwing herself in front of a horse at the same course.
Some spectators cheered as the protesters were taken away, with a voice on a loudspeaker apologising to spectators.
On Thursday, other members of Animal Rebellion were arrested after they entered the ceremonial route on the Mall before trooping the colour.
The group said the protest was aimed at making “a definitive statement, and act, against the cruelty and harm the horseracing industry represents”.
It describes itself as a “mass movement using nonviolent civil disobedience to call for a just, sustainable plant-based food system”.
The group is demanding “an end to horse racing, all forms of animal exploitation, and instead a transition towards a plant-based food system and animal justice”.
Orla Coghlan, one of those at Epsom, said: “Horse racing took the lives of 220 animals on racecourses in the UK last year, and this is just the tip of the iceberg.
“In this country over a billion land animals are killed for food each year. Exploitation of, and violence against, animals is fuelling the climate emergency and suffering across the globe.
“It is obvious we must choose life over death and stop animal exploitation.”
The Queen’s daughter Anne was there at Epsom alongside husband Vice Admiral Sir Tim Laurence and children Peter Phillips and Zara Tindall, who was with husband and former rugby player Mike.