Bad time to ask Nate Dogg for child support ... he's dead.
A woman named Shereda Williams -- one of Nate's multiple baby mamas -- just filed a creditor's claim against Nate's estate, claiming it owes her $339,924 in unpaid child-rearing money.
The hip-hop legend allegedly was supposed to pay Shereda $4,358 a month, but she claims he never made a single payment. Their child was born in 2006 ... Nate passed in 2011.
Shereda says the estate of hip-hop's Hook Man now owes her the outstanding balance, including payments that have accumulated since Nate died.
Unfortunately, Nate was pretty short on cash before his death ... so it might be a while before she gets paid ... possibly an eternity.