Hannah Southwell completed the 2026 NRLW season with 55 career appearances after playing all 11 matches for the Dragons.
She reached her 50th game against the Wests Tigers in Round 6.
St George Illawarra and Southwell have mutually agreed to release her from the remainder of her playing contract, after discussions between the club and player.
Southwell had played nine games for the Red V in 2025 and had two stints with the club.
Dragons Director of Female Football Sammy Bremner thanked her for her contribution and noted her place in the club's foundation squad.
"Hannah has been part of some important moments in the history of the NRLW program, including as a member of the foundation squad," Bremner said.
Bremner also wished Southwell and her family well for the future.
"We thank Hannah for her time at the Dragons and wish her and her family all the very best for the future."