"I just pushed the whole thing out of my head," the rapper writes in a new memoir.
Common has revealed he was molested as a child but didn't remember the traumatic experience until recently.
In his new memoir, "Let Love Have the Last Word," the Oscar winner opened up for the first time about being sexually abused. Common said he recalled the disturbing memory while preparing with Laura Dern for their roles in "The Tale" two years ago. The critically-acclaimed HBO thriller centers around a woman's childhood sexual abuse.
"One day, while talking through the script with Laura, old memories surprisingly flashed in my mind," Common wrote according to an excerpt obtained by People. "I caught my breath and just kept looping the memories over and over, like rewinding an old VHS tape...I said 'Laura, I think I was abused.'"
The "Selma" star explained how the abuse happened when he was only 9 or 10 years old while visiting his aunt in Cleveland, Ohio.
"I was excited for a road trip I was about to take with my family," he recalled in the book. "My mother; my godmother, Barbara; her son and my godbrother Skeet; and his relative, who I'll call Brandon..."
Common said the incident occurred when he and Brandon shared a bed together one night. "At some point I felt Brandon's hand on me," he recalled in the memoir. "I pushed him away. I don't remember saying a whole lot besides 'No, no, no.'"
He continued, "[Brandon] kept saying 'It's okay, It's okay,' as he pulled down my shorts and molested me. After he stopped he kept asking me to perform it on him. I kept repeating 'No' and pushing him away. I felt a deep and sudden shame for what happened."
The Grammy winner said he doesn't think he remembered the trauma until now because he "buried" the painful experience. "I just pushed the whole thing out of my head," he wrote. "Maybe it's a matter of survival-- Even now, two years after that flash resurgence of memories, as I'm writing, I'm still working through all of this in myself and with my therapist."
While appearing on "GMA" Tuesday, Common said he decided to share his story to help others who have been abused.
"It was something that I didn't know if I wanted to talk about," he told ABC's Robin Roberts. "But I really believe that in telling my story, other people will be OK with talking about that situation."
"We don't talk about those issues in ways that we could," he added. "So I felt I wanted to create a space for people who have experienced that to be able to share that. That's part of the healing, to be honest. No sooner than I told the story, one of my good friends came out and told me it had happened to him."