Radcliffe spoke out in support of Watson, and her HeforShe campaign to promoting equality between men and women, reported People magazine.
"I think it's fantastic that she's bringing attention to it and adding to the conversation," he said.
Watson's campaign asks men to throw their support behind gender equality, with the idea that equal rights for women cannot become a reality without advocates from both genders.
Radcliffe said he finds the issue "bemusing, honestly, maybe because I have cool parents with a very equal marriage and have had good role models all my life. "I thought this was done," he added.