John Barrowman wants the BBC to "go out on a limb" and cast the next Time Lord as a woman.
Matt Smith is currently filling the role, the eleventh regeneration in nearly fifty years.
When asked by the Press Association if there should ever be a female Doctor, the Torchwood star replied: "I think a female doctor might work, you never know. The audience might not like that. I know there's a lot of young girls and women who would love that.
"I think that maybe they should go out on a limb next time and try it. That always stirs things up a little bit and makes things exciting and it's nice to see different things and challenges happen like that.
"Listen, if Captain Jack can be an omni-sexual time agent and an assistant to the doctor, why can't we have a female doctor?"
As for who he saw in the role, Barrowman said: "I have no idea. I always thought Catherine Tate would make a lovely female doctor, if they did something with her character, but I don't know, I have no idea.
"Put me in a dress and I'll be the female doctor."
When asked to give his opinion on Smith's performance, Barrowman replied: "Matt has put his mark on it and rightfully so and he's a wonderful doctor, but my doctor will always be David (Tennant)."
Doctor Who is currently showing on BBC1 on Saturday nights.