Polkinghorne, who has been with the Roar in every season in the Westfield W-League, became the first player to reach 100 appearances in Australia's elite women's club football competition.
The home-grown hero has had a stellar career in Brisbane since making her debut as a foundation player at the age of 19 and was a key contributor in the Roar's 2008-09 and 2010-11 Championship winning teams'.
Meanwhile, Mackenzie Arnold has also committed her future to Brisbane and continues to enhance her reputation as an integral member of the current squad after joining from Perth Glory last season.
The 23-year-old stopper's recent performances have not gone unnoticed, with Arnold recently being named in the successful Matildas 2017 Tournament of Nations squad and for the upcoming home series against football powerhouse Brazil.
Head Coach Melissa Andreatta is delighted to see Polkinghorne and Arnold continue their football careers in Orange.
"To have Clare and Mackenzie as part of our squad for season 2017/18 is great news for our Club," Andreatta said.
"We are excited for what lies ahead and I'm sure both players will have a positive influence on our group once again.
"They are leaders of our team and demonstrate the commitment and passion that we require for the upcoming campaign."
Both Polkinghorne and Arnold will return to Brisbane to begin pre-season training after taking on Brazil on Saturday, September 16 in Penrith and on Tuesday, September 19 in Newcastle.
Season 10 of the Westfield W-League competition will begin in late 2017 with Mel Andreatta's side looking to pick up a third Championship.
More details about the Roar Women 2017/18 squad will be released over the coming weeks.