The midfielder has been at Rangers for five years and will stay on as captain in the new-look women’s squad for the 2020 campaign.
The 33-year-old has been influential in the centre of the pitch in recent years, captaining the side for the past four seasons.
Women’s and Girls’ Football Manager Amy McDonald said: “Having Clare as part of this new team was vital to us. She understands the club and the values that we hold close to our heart at Rangers.
“Her hard work and dedication to the cause at Rangers is admirable and she remains a key part of our squad. Tying her down for another six months is another positive step on our new journey for 2020.”
Gemmell commented:
“I’ve obviously been here for a number of years and I just like the set-up and the culture of the club.
“It has been really positive during my time here and it is only continuing to get better so it is definitely somewhere that I see myself finishing my career.”