The former NSW Government minister died, aged 75, after a long battle with illness.

Racing NSW's chief executive Peter V'landys AM was among the first to pay his respects.

"Paul was a visionary and admired by all," he said.

"He was respectful to anyone he met, on any level, and always had a smile on his face.

"Paul will be missed by everyone in the racing industry that had the pleasure of his acquaintance and we would like to pass on our sincere condolences to his family."

Mr Whelan was born and raised in Ashbury, a suburb of Sydney, and was the last of seven children.

He was admitted as a solicitor in 1968 and barrister in 1988, then became an alderman on Ashfield Municipal Council from 1970 and was mayor from 1971 to 1976.

Mr Whelan went on to become NSW Minister for Consumer Affairs and Minister for Roads in 1981 and then Minister for Water Resources and Minister for Forests until April 1984 for the Neville Wran government.

He was also Minister for Aboriginal Affairs in 1984 before becoming Minister for Police from April 1995 to November 2001 during the Bob Carr era.

Upon retirement from politics, Mr Whelan went into racehorse breeding and racing, and was proprietor of Luskin Park Stud, a boutique stud at Luskintyre in the Hunter Valley.

He was also on the committee of Thoroughbred Breeders NSW.

He bred some top-class performers including Foxwedge and Rock Classic, and also part-owned Group One winner Flying Artie with his long-time friend, Wilf Mula.

"Paul was a great man and above all, a caring human being," Mula said.

"We went to school together and once he got out of politics, he went into breeding racehorses which was his passion.

"He actually got me into racing when he had Pegasus Queen with Bart Cummings.

"Paul had a good eye for horses and bought Flying Artie then told me I 'had to come into the horse' with him.

"I'm glad I listened as Flying Artie was an outstanding galloper and is now an up and coming sire.

"Paul was an outstanding person and will be missed by many."

Mr Whelan is survived by wife Colleen and his extended family.