Mel B's Ex Stephen Belafonte Wants Piece of Spice Girls Tour Money

Mel B's ex-husband says she needs to share the fat wad she earned on tour with her Girls, 'cause it's A LOT ... and he deserves a cut to help care for their kid.

Stephen Belafonte filed new docs asking a judge to modify how much Mel pays him monthly for child support -- currently $5,000/mo. -- because he says she recently raked in a massive amount of money from this year's Spice Girls reunion tour.

How much we talkin'? Stephen says Mel alone, by her own admission in court records, made around $2.4 million.

We broke the story ... all the singers stood to make upwards of $3 million each by getting together again on the road. Scary Spice's payday was a little short of that, but still enough for Stephen to come a-knockin'.

In the docs, obtained by TMZ, Stephen claims Mel has tried to skirt including that dough as part of her regular income. He says, instead, she reported it as a one-time sum. Stephen's calling BS and wants some of that income increase should translate to a child support boost to $17,394 per month. He's also demanding she cover his attorney's fee.

Of course, Mel and Stephen already settled their divorce with agreed-upon payments and a custody schedule, but they're going back to court next month to hash this one out.