The Brooklyn Zoo event at Lakota, in Stokes Croft, Bristol, invited people to pay homage to their favourite rapper with "murky face paint" and toy guns.
The club apologised saying it took "immediate steps" after its Twitter feed became "full of complaints".
The promoter has yet to respond but on its Facebook page has requested outfits are kept "appropriate".
The Dead Rappers Halloween Party was promoted by Brooklyn Zoo as a chance to "pay homage to your favourite rapper that ain't with us no more".
Clubbers were invited to "get involved" with "fake blud, hella bling, murky face paint 'n a toy gun".
Bristol University student Juliette Motamed said: "The 'murky paint' - are they implying black face or are they just explicitly saying it but trying not to get caught out?
"And who thinks "Dead Rappers" is an appropriate genre."
Chante Joseph tweeted Bristol City Council asking it to investigate the "racist Halloween event" and said she hoped "students dressed in black face" would not be allowed in.
While Damilola Odelola tweeted that "even if they're not [in black face], this is extremely racist".
But Lakota said it had not agreed the theme or the way it was promoted and apologised for "any offence that has been caused".
"It wasn't until we started receiving complaints that I took a look at the advertising and immediately got on the phone with the promoter," said Marti Burgess, Lakota's owner.
"The whole concept of people dressing up and painting their faces - we've been through that as a country and as a society - it's not appropriate."
The event is still due to go ahead as a Halloween Hip Hop Night and promoter Brooklyn Zoo has said on its Facebook page that "any outfit that's deemed offensive, racist or inappropriate in any way will not be granted entry at all".
A nightclub has apologised after adverts for a Halloween "Dead Rappers" fancy dress party were branded racist.