Leonardo DiCaprio and Vittoria Ceretti Have Dinner With Her Family in L.A.

Leonardo DiCaprio is a real family man when it comes to Vittoria Ceretti ... because Leo was out to eat with his chick's parents and siblings.

The actor and his model girlfriend sat down for a family dinner Thursday night in Los Angeles ... hitting up Anajak Thai Cuisine in Sherman Oaks.

Leo was dressed in all black with his trademark ballcap and face covering ... keeping a low profile before the family gathering.

Vittoria looked stunning as always ... arriving separately from Leo and leaving at different times too.

We've seen Leo and Vittoria having a good number of family outings this year, but they usually just grab a bite with their parents ... and now Vittoria's siblings are entering the fold.

Check out the gallery ... it looks like a good time was had by all.

Something tells us Leo picked up the check, BTW.