A small group of people have staged a protest outside the Liberal Party's pre-selection meeting for former treasurer Joe Hockey's seat of North Sydney.

Mr Hockey held the safe seat for almost two decades, before his decision to quit politics in the wake of the Liberal leadership coup.

Two main candidates are vying to win Liberal Party endorsement for the seat including acting New South Wales Liberal Party president Trent Zimmerman and John Hart, head of Restaurant and Catering Australia.

Half a dozen protestors held up banners outside the Chatswood venue claiming the pre-selection process has been rushed and undemocratic.

The protestors refused to say whether they were Liberal Party members or supporters.

Former NSW Liberal Party MP Bruce Baird, father of Premier Mike Baird, said while everyone has a right to protest, the pre-selection process had been fair.

He said from his recollection it was advertised on the party's website almost a fortnight ago.

Former Treasurer Joe Hockey held the safe Liberal seat for almost two decades. ( AAP/Lukas Coch )

"I thought that's strange because Joe hadn't resigned yet but they obviously knew it was coming and so everyone knew about it," he said.

"'People can feel that maybe we could have had longer but I doubt whether it would have changed anything."

Asked whether better candidates would have emerged with more time, he said the existing candidates were "excellent".

"We couldn't do better in terms of the field," Mr Baird said.

He refused to reveal which candidate would get his vote in the pre-selection.

Whoever wins the vote tonight still has to be endorsed by the Liberal Party state executive.

The by-election is to be held on December 5.