Protesters will take a stand outside the Boxing Day Races today, arguing the sport is "fundamentally cruel".
The Coalition for the Protection of Racehorses (CPR) says activists will demonstrate at the Ellerslie Racecourse from 11am with placards and banners in a bid to get racegoers to reconsider supporting horse racing.
They will also demand the industry "at the very least" implements a retirement plan for the horses.
CPR spokesperson Aya McKenzie said the group was "vehemently opposed" to horse racing because every aspect of it is fundamentally cruel to the race horses before, during and after their racing careers.
"Under coercion by a jockey wielding a whip, nearly all race horses will sustain injuries directly as a result of being pushed too far," McKenzie said.
"It's unconscionable that a sport that purports to love their horses allows this to happen in the first place but then the ultimate betrayal comes when the horse is no longer profitable and, in most cases, will be condemned to slaughter."
She said CPR wanted people going to the races to know "it's no fun and games" for the horses competing.
"Punters lose their money while it's costing horses their lives," she said.
"We're urging people to think twice. Don't go to the races, instead find another cruelty-free activity to do these holidays."
The Boxing Day Races is an iconic part of the Auckland social calendar, running for more than 160 years.
It features 10 races, food and entertainment, and a fashion competition.