The 48-year-old Justice League star's 9-year-old son Samuel looked overjoyed to see his dad when the actor showed up to his swimming lessons in Los Angeles on Tuesday.
Affleck matched his child's excitement by greeting him with a big bear hug as photographers snapped away.
J Lo's boyfriend kept it casual for the pick-up, wearing a burgundy graphic tee, black jeans, and sneakers.
Affleck kept his face mask on, despite California loosening the mask restrictions this week.
The Academy Award winner was clearly thrilled to see his youngest kid, who he shares with ex-wife Jen Garner.
He was seen opening his arms wide before bending down to embrace Samuel.
The duo clearly had some catching up to do because after their bear hug, Affleck leaned down and looked deep in conversation with his son.
Their adorable father/son moment comes on the heels of Affleck's PDA-filled dinner with J Lo.
As Radar reported, the couple enjoyed a meal with the Love Don't Cost a Thing singer's 13-year-old twins, Max and Emme, on Sunday in Malibu.
Despite not being able to keep their hands -- or mouths -- to themselves, J Lo's son and daughter bonded with their mom's new boyfriend over the family dinner.
"Ben and her kids seemed comfortable together," an insider told PEOPLE. "The kids kept chatting with Ben. Ben seemed great. He was smiling and laughing. They ordered a lot of food to share. Ben had a Diet Coke."
"They enjoyed a Sunday family dinner together," the Nobu source continued.
"Jen and Ben sat next to each other and were very affectionate," they added. "They held hands under the table." Photos later emerged and backed up the PDA claim.
Following his lovely dinner with J Lo and her children, Affleck reunited with his ex-wife to celebrate their middle daughter's six-grade graduation on Monday.
Affleck and Garner share three kids together -- Violet, 15, Seraphina, 12, and Samuel.
Despite their awesome co-parenting skills, Garner is said to not want anything to do with the circus surrounding Bennifer.