Love and Bock shared the news Sunday ... posting adorable pics from just after the NBA star popped the question -- and check out the ring, it's huge!!!

Sources close to the couple tell us ... the proposal went down Saturday night at a private outdoor dining space at Lilia restaurant in Brooklyn.

As for the ring ... we're told it's a vintage diamond cut from the 1930s for Cartier and it’s set in a chic vintage Cartier setting. Kevin worked with a jeweler out of London to get it done.

"'Souls tend to go back to who feels like home,'" Love wrote alongside the engagement announcement on social media. "My fiance. The Joy of My Life."

Bock, who was celebrating her 33rd birthday when Love asked her to marry him, added, "Well, this was the best birthday surprise I could have ever imagined."

"I couldn't be happier to have been asked to be a Love by my love. Heart bursting all day & night."

Bock and 32-year-old Love have been dating for about five years now ... and they've been one of the most precious celeb couples.

The two have gone on all kinds of romantic trips together -- and have even shared a love for a Vizsla dog named Vestry, who's become one of the most famous pups on the internet.

Several NBA stars commented on the couple's engagement Sunday, with Love's former teammate, LeBron James, writing, "Congrats my brother!!!"

Cheers!!!!