Kevin Federline is Making REAL DJ Money Now ... Overseas

Kevin Federline is NO joke in Japan -- in fact, the man who built a kingdom down the street from Pepperdine is about to get his biggest DJing paycheck ever ... in Tokyo.

Britney's ex booked a two night gig at Cat's -- the nightclub, not the play -- where he'll man the DJ booth for their annual Halloween bash on Oct. 23rd and 24th.

K-Fed's first trip to Tokyo will be well worth it -- the weekend gig pays $15k ... or about ¥1.7 MILLION! Last time we checked, K-Fed was only bringing home $1,000 per gig, so this is a huge step up.

If Tokyo reacts anything like Portland did last weekend, he'll have 'em chanting ... "K-Fed ichiban!"