The comedian told ESPN Radio New York host Mike Lupica that he can barely keep a straight face while filming scenes on Curb Your Enthusiasm.
"Well, I've always had fun doing the show, and I guess that's why I keep doing it after eight years," David said. "It's hard for me to do a take without laughing really."
Previous seasons of Curb Your Enthusiasm have been focused on Larry's possible adoption and a fictional Seinfeld reunion, but David insists that the success of the show's eighth run may be due to a lack of any story arc.
"If I could point to one thing it's probably that we don't have a story arc this year, that all the shows are sort of independent except for going to New York - that's really the only little story we have going this season. But other than that, that's it," he explained.
David also revealed that he hasn't decided yet whether Curb Your Enthusiasm will return for a ninth season.
Last month, David compared the fictional version of himself that he plays on the HBO comedy series to Superman.
Curb Your Enthusiasm continues with new episode 'Car Periscope' on Sunday on HBO.
> Jerry Seinfeld: 'Curb Your Enthusiasm return unlikely'
> Curb Your Enthusiasm star Jeff Garlin working on ABC comedy
Watch a trailer for the next Curb Your Enthusiasm episode below: