The 26-year-old pop singer made the announcement in an Instagram post Wednesday.
"surprise! 🍼🌈👼🏻," she captioned the post.
It was not clear how far along in the pregnancy she was, nor who the father is.
An Edison native, Halsey -- whose birth name is Ashley Nicolette Frangipane -- graduated from Warren Hills Regional High School in Washington in 2012.
She began writing music while living on Halsey Street in Brooklyn when she was 24 years old.
Halsey quickly rose to fame with hits like "Eastside," "Closer" with The Chainsmokers, "Graveyard" and "You Should Be Sad."
The vocalist denied claims she was pregnant in November 2019.
Click here to follow Daily Voice Edison and receive free news updates.