Emergency services were called to the site about 11.30pm Tuesday night following reports of a fire in the main bar.

Trangie-based mayor of Narromine Shire, Bill McAnally, was called to the fire in his role as a volunteer firefighter with the Rural Fire Service.

"I had been attending to a re-ignition of some trees that had been on fire after a lightning strike the night before when I got a call to say the pavilion was on fire," he said.

"NSW Fire and Rescue personnel had arrived and taken the sting out of it by the time we got there.

"Firefighters managed to save the big community hall at the racecourse that council and the community had spent $150,000 to restore."

A spokesperson for Orana Local Area Command said police were treating the blaze as suspicious.

Councillor McAnally said he could not understand why someone would set fire to the facility.

"The community has built this together and is so proud of it," he said.

"We have two race meetings a year here, and people hold weddings and other celebrations here.

" Why destroy property that community groups have busted their guts to build?"

Anyone with information about the incident has been urged to contact Narromine Police on 6889 1444 or Crime Stoppers on 1800 333 000.