The singer criticised the Bajan performer's lyrics and insisted they are not good for young girls, but admitted that she is a "brilliant popstar".
Young told OMG!: "I don't think Rihanna is a massively great role model for women, her lyrics aren't empowering.
"She's a brilliant popstar and recording artist but her lyrics are not empowering - young girls have to listen to those lyrics."
He continued: "I saw Rihanna kissing a girl in one of her videos ['S&M'] and I thought, 'Who is this for? If you're going to do it just go the whole way like Madonna did and have sex on a bed'.
"Women in a patriarchal society should be empowering and owning their bodies; I don't think Rihanna is. I feel quite strongly about this."
However, Young praised Lady GaGa for owning her female sexuality. He added: "Image-wise Lady GaGa is empowering.
"I'm more interested in women like Annie Lennox or Grace Jones, people who have challenged the female form, who have owned it and brought it forward."
Will Young's new single 'Losing Myself' will be officially released in the UK on March 19.
> Will Young unveils behind-the-scenes look at new video 'Losing Myself'
> Will Young: 'I'll be a strict father'
Watch the music video for Will Young's 'Losing Myself' below: