The 42-year-old took a break after giving birth to her twins, Moroccan and Monroe, in April 2011. She is married to singer Nick Cannon.
Her last album was "Merry Christmas II You" in 2010.
In December last year, she collaborated with Justin Bieber on the re-release of her festive hit "All I Want For Christmas Is You". But now she is back with full force, Carey announced on Twitter, reports femalefirst.co.uk.
"Summer 2012... Been in the lab, mixing up some concoctions for you, hope you like it! Still working in the studio with friends oh plenty! I love this new song," she tweeted.