Grant said he had approved regulatory changes to support a minimum bet rule implemented by Racing NSW on 1 September 2014.
"The introduction of a minimum bet limit by Racing NSW followed regular complaints by punters that some wagering operators were refusing to take their bets, particularly if they had a winning record," Grant said.
"The new Racing NSW condition requires wagering operators to be prepared to take on a bet for a minimum amount on any single fixed odds wager on NSW thoroughbred races.
"This is the same rule that applies to on-course bookies and maintains the integrity of thoroughbred racing.
"Some online bookmakers have refused to express unqualified support for the new minimum bet rules and therefore the NSW Government is making a regulation to enforce the new minimum betting rules.
"I applaud Racing NSW for their nation leading push to ensure punters get a fair go."
Under the September 1 change, wagering operators with a thoroughbred turnover of $5 million or more must be willing to accept at least one bet from a punter wanting to win up to $2,000 on a metropolitan race ($800 for a place) or $1,000 at a nonmetropolitan race ($400 for a place).
In addition, wagering operators with a thoroughbred turnover of less than $5 million must be willing to accept at least one bet from a punter wanting to win up to $1,000 at any thoroughbred race ($400 for a place).
"Racing NSW has also established a complaints mechanism for punters who believe they have been unfairly treated by a wagering operator," Grant said.
"It is not fair to have wagering operators profit from punter losses but then bar or restrict successful punters in the amount they can wager on any one bet. Shutting out punters impacts racing's reputation and potentially distorts betting markets."