Ben Affleck and Jennifer Lopez did a little blending Saturday ... as the love train chugged through Westwood.
Ben and Jen hit up the Regency Theater with his kids, Seraphina and Sam, and her daughter, Emme.
They took in a showing of "Licorice Pizza" and looked like a fam out for a day of fun.
They got celeb treatment for sure ... an attendant was right there to escort them in through a side door and warn them all to step away from some puddles.
The kids have been seen more and more with J Lo and Ben ... over Thanksgiving, they were all involved in a food drive in L.A. ... loading and unloading sacks of food. The event was part of Rise Against Hunger ... a problem that has reached crisis proportions in L.A. and many other cities.
As we reported, Ben and Jen have been house hunting for months now, even though both own homes in L.A. The hunt, we're told, is for the 2 of them to move in together, so getting the kids together in different combinations is clearly a smart idea.