The former Michigan State doctor, who was sacked by USA Gymnastics in 2015, was previously accused of sexual misconduct by Raisman's fellow Fierce Five member McKayla Maroney and Sydney bronze medalist Jamie Dantzscher.
Raisman says a lot of people have asked her why Nassar's accusers didn't speak up sooner.
More than 140 women are now suing Nassar and his former employer, Michigan State University.
Now, however, Raisman is talking about her own experience, telling 60 Minutes: "I just want to create change" so other young girls "never, ever have to go through this".
RAISMAN: I am angry.
Dr. Nassar accepted a plea deal in July that would have him serve a combined sentence of 22-27 years for possession of child pornography, rather than charge him with sexual assault - a widely criticized move prosecutors justified by saying that numerous allegations they heard occurred overseas, where they have no jurisdiction.
Raisman is demanding that the USA Gymnastics change its policies following the allegations against Nassar, according to Fox News.
Raisman, who won six medals at two Olympic games, including three gold medals, said she was first treated by Nassar at the age of 15. I can't. Every time I look at them, every time I see them smiling, I just think ...
BC-GYM-Raisman-Sexual Abuse, 5th Ld-Writethru, 724 Olympic gymnast Aly Raisman: I was abused by doctorAP Photo NY903, NY166, NY167Eds: Adds new photo of Dr. Larry Nassar.
Raisman, the captain of the 2012 and 2016 Olympic gold-medal winning teams, details the abuse in her book "Fierce", which will be released on Tuesday.
"We are committed to doing what is right, and we want to work with Aly and all interested athletes to keep athletes safe", USA Gymnastics said.
In her tweet, Maroney mentioned a specific instance of sexual abuse when she was 15 years old, in which she alleges Nassar gave her a sleeping pill on a team flight and assaulted her in his hotel room upon landing. "And then he just continued to go into more and more intimate places", Jessica Howard, who suffered from severe hip problems when she was a gymnast, told CBS' 60 Minutes in an episode that aired February 17.
"Dr. Nassar is no longer affiliated with USA Gymnastics". Raisman and Maroney have both said that Nassar's harassment came in the form of "treatments".
In July, the organization hired Toby Stark, a child welfare advocate, as its director of SafeSport.
In June, the federation immediately adopted 70 recommendations proffered by Deborah Daniels, a former federal prosecutor who oversaw the review. Part of Stark's mandate is educating members on rules, educational programs and reporting.
It is also reported he still faces 33 charges of criminal sexual conduct in MI. USA Gymnastics now has the power to withhold membership from clubs that decline to report claims of abuse.