The news was shared by Astin on his Instagram account, reported People magazine.
"I asked. She said yes!!!" Astin, 28, wrote along side his and Camp's picture.
Camp, 33, replied by putting up the same photo with her flashing the ring, "He asked. I said YES!!!!"
The couple have been dating since June 2013.
Both starred in 2012's "Pitch Perfect".
Camp was previously married to actor Michael Mosley and the pair filed for divorce in 2013.