Isobel Borlase (born 12 September 2004) is an Australian professional basketball player for the Melbourne Tigers of the NBL1 South.

[4] She played junior basketball for the Forestville Eagles[5][6] and led South Australia Metro to victory at the 2021 Australian Under-18 Championships.

[8] Borlase joined the Basketball Australia Centre of Excellence in 2021,[9] where she played in four games in the Waratah League.

[4] In January 2022, Borlase joined the Adelaide Lightning of the Women's National Basketball League (WNBL) for the rest of the 2021–22 season.

[16] She entered WNBA draft pick discussions in her second full season, and with team captain Stephanie Talbot sidelined, she began shouldering more responsibility.

[26] Choosing to remain in Adelaide for another 12 months,[27] Borlase joined the Forestville Eagles for the 2024 NBL1 Central season.

[34] In 2022, Borlase helped the Gems win the gold medal at the FIBA Under-18 Asian Championship in India.