The Roosters have written to their members to warn them about bad behaviour following "unacceptable" conduct at recent home games including an incident with model Sophie Monk.

The warning comes ahead of the Roosters' top of the table clash against Brisbane at Allianz Stadium on Saturday.

Fairfax Media has obtained a copy of the email sent to the club's members on Friday. The Roosters, who have 16687 members, reminded their fans of the club's code of conduct.

"Unfortunately at recent home games some members have experienced levels of unacceptable behaviour from a minority of Sydney Roosters fans," the email read.

"We take this opportunity to remind our members of the Sydney Roosters 'code of conduct' to which all members are required to comply."

The reminder comes after Monk was allegedly assaulted by a shirtless man when the Roosters hosted the Eels last Saturday. Monk, who was dressed as a pizza, was filming an episode of the reality TV program The Celebrity Apprentice at Allianz Stadium when she was grabbed on the bottom by the man. 

Roosters chief executive Brian Canavan said there had been a "slight increase in incidents" of disrespect towards fellow patrons.

"It's a reminder," Canavan said of the email. "The key words in our code of conduct is respecting others.  It's more or less been [bad] language and manners. We've noticed an increase and the stadium staff, who interact with us as the tenant on that day, have given us that feedback.

"It's one that's been building up. Generally speaking our members self-regulate. We just needed to remind those people who are not engaged on a frequent basis as our avid members."

According to the club's code of conduct, the Roosters can cancel a fan's membership if they break any of the seven points which make up the code.

They are: to work with the club to enforce the code of conduct at all games, respect and welcome opposition fans to the venue, not to abuse or use bad language, understand that anti-social behaviour will not be tolerated, there is a zero tolerance towards racism and discrimination, to advise security of any anti-social behaviour and abide by the conditions of entry of the Sydney Cricket and Sports Ground Trust.

One Roosters member said behaviour last Saturday was disappointing.

"The crowd's attention was focused away from the field and to a man who had clearly had too much to drink and was starting to take his clothes off," the member said. "Unfortunately I see this sort of behaviour at almost every home game and I'm so embarrassed as a Roosters member that this has become an almost expected part of the night. It's not appropriate, it brings shame on the club, and I believe it's a huge reason why families are turned off from going to live NRL games."