According to CNN, Keys and her fiance rapper Swizz Beatz announced the good news after weeks of speculation.
The couple has been dating since 2008 and is expected to marry in a private ceremony later this year, reports News.com.au.
Beatz, 31, whose real name is Kasseem Dean, has two sons from previous relationships.
The publicist did not mention the time when their child was expected.
Photographs: Phil McCarten/Reuters