Santonio Holmes' Baby Mama -- I Want MORE of Your Millions

Touchdown-machine Santonio Holmes better not get too attached to his giant new paycheck from the Jets -- because TMZ has learned, a woman he knocked up back in 2002 wants a fat raise ... in child support.

Just months after Holmes signed a 5-year deal with the Jets worth nearly $50 million, a woman named Nicole King has filed a petition in Florida for child support modification ... demanding way more money from the star wide receiver.

King cites Holmes' new contract in the docs -- claiming, "There has been a substantial change in circumstances in that [Holmes'] income has substantially increased since the entry of the final judgment and the needs to the child have increased."

King doesn't specify how much extra cash she wants now that Holmes is rolling in more dough than ever -- but according to the current child support order, Holmes is already required to pay the woman $4,000 a month ... and even buy her a house.