The incident happened in a Super W clash between Patu's Queensland side and Western Australia on Saturday. Video replays showed Patu sinking her teeth into the arm of Wallaroos teammate Rebecca Clough late into the match.
Clough informed the referee of the incident but the official stated they didn't see it happened.
Patu pleaded guilty to the charge during an hour-long hearing last night and said in a statement her actions were 'unacceptable'. She apologised to Clough.
Facing a maximum 12-week ban, Patu received a 50% reduction given her previous clean record and good character.
"I'd like to express my remorse for my actions in Saturday's match," Patu said in a statement released by Rugby Australia.
"I apologise to Rebecca Clough, the Rugby WA women's team, my own teammates and the wider rugby public.
"I've played club, state and international rugby and previously haven't committed an act such as this and I accept my punishment.
"I want to reassure the rugby public, administration and my fellow players, that when I return to play I will ensure that the game is played in the right spirit and do what I can to promote the women's game in a positive manner.
"My actions the other night were unacceptable and will not be repeated."
Former Wallabies player Drew Mitchell was commentating the game and called the act 'disgusting'.
"That's pretty damning from that vision we've just seen," Mitchell said.
"I think we will hear more and we should.
"That is disgusting and it's not a part of our game, especially from an Australian representative and a captain at that."
