Long before he started producing tracks for Jay-Z, Chris Brown and Drake — and before he whisked Alicia Keys away to get married on the Mediterranean — Swizz Beatz was just a skinny kid trying to make a name for himself.

And he couldn’t make a name for himself fast enough, which is why he started working the club scene long before he was old enough to order a drink from the bar.

“When I was 17, I started off DJing for the high school prom, then I started DJing the college parties, then I started DJing the clubs,” Swizz reveals on the upcoming episode of MTV’s “When I Was 17,” which airs Saturday at 11 a.m. “I’m not even 21 yet.”

But the precocious mix-master worked out a system to ensure he’d always be able to get into the club and behind the turntables.

“Usually, I would go through the back of the club, because of my age, and set up, so when people come in, there’s no questions, there’s no ID,” he says.

And he usually stuck to that foolproof system — except that one time.

“One day, I sent one of my guys to set up for me,” Swizz explains. “So I go through the front, I get to the door and — ‘Show me your ID!’ I’m like, ‘I don’t have no ID. What do you mean, show you my ID? I work here. I’m supposed to be getting the party started.’ “

And if it’s one thing Swizz knows, it’s getting a party started. He’s produced tunes with the likes of Chris Brown and Lil Wayne (“I Can Transform Ya”), T.I. (“Swing Ya Rag”) and even a Jay-Z/U2 collaboration to benefit relief efforts in Haiti. But on this one night when he was 17, there was simply nothing Swizz could do to sneak his way into the club.

“I was like, ‘I’m telling you, I work here!’ ” he recalled. “I’m speaking with so much authority. I’m this little skinny guy. He’s looking down on me, like, ‘I don’t care. Step over here.’ “