Attention Harry Styles: Mark Wahlberg is watching you.

Appearing as a guest on Thursday night's "Conan," Wahlberg lamented the fact that his daughters have become Directioners — with the suave Styles drawing the majority of their affection. And that puts him square in the sights of the rough-and-tumble actor, who's determined to take matters into his own hands, if necessary.

"Now the girls have turned to One Direction, and, it's like they don't care about dad anymore," Wahlberg told O'Brien. "My 4-year-old is going 'Daddy, I like Harry.' And I'm like 'Well, I'm going to punch Harry in the nose when I see him.'

"She pulls out pictures of him and she's hiding pictures in the room, and I pretend that I'm going to rip them up and I get jealous," he joked. "But if I see that little prick, he's gonna get it."

And just in case Styles' bandmates are reading this and laughing, well, they probably shouldn't. Turns out they're not safe from Wahlberg's rage, either ... and, now that he's starring in the upcoming "Transformers: Age of Extinction," let's just say they probably shouldn't take any calls from director Michael Bay any time soon.

"I could say 'Hey, I really want to meet One Direction, I'm a big fan.' Invite them to the 'Transformers' premiere, [tell them] 'Maybe you can do the title track," Wahlberg said. "And then I'm going to beat the crap out of them at the video shoot. Probably all five of them."

No wonder Styles was recently spotted trying to flee Los Angeles in Kendall Jenner's car.

In all seriousness, Wahlberg was clearly joking. In fact, he's going to try and make a meeting with 1D happen ... if only so he can get it out of the way while his daughters are still too young to date.

"You know what? I am going to try to get my daughters to meet them; I'd rather do it now," he said. "My oldest is 10, she's into them as well, and that would be the only time I'll ever introduce them to a boy."