Delivered as Eminem's dark performance alter-ego Slim Shady, Rap God features violent, bravado lyrics that taunt his rivals in the aggressive style for which the Grammy Award-winning Detroit rapper is known.
At issue is his insulting use of the words "gay" and "f-ggot" throughout several sections of the track.
A host of music critics and media outlets praised the song (which emerged last week in advance of his upcoming album The Marshall Mathers LP 2), but many have also blasted the rapper for the language, which has been criticized as being homophobic.
British singer and DJ Boy George and LGBT rights groups are among those who have criticized Eminem for this latest release, calling it a return to outdated views and past offensive music.
The chorus of criticism was joined most recently by rapper LastO and singer-songwriter Solomon, two of the openly gay hip hop recording artists featured in a month-long series on Eminem's satellite radio channel in 2008.
"When he invited me on his radio station a few years ago, I thought he put all of this aside," Solomon said in a statement.
"Granted, it's not directed towards the gay community, but subconsciously it is. He's using the word f-ggot to degrade another man. As if the worst thing a man can be is gay. What type of message does that embed into the minds of young kids, both gay and straight?"
The controversy over Rap God arrives after the rapper's repeated declarations that he has "nothing against gays" (including in a 60 Minutes interview with Anderson Cooper in 2010) and his high-profile Grammy Awards performance alongside Elton John in 2001. Eminem has not commented publicly about the reaction to the song.
Acceptance of LGBT artists in the hip hop community has been an increasingly prominent issue over the past year, in part tied to rising hip hop singer Frank Ocean's 2012 revelation about falling in love with a man and exemplified in this summer's hit Macklemore and Ryan Lewis marriage-equality track Same Love.
"As irreverent and offensive as [Eminem's] brand is supposed to be ... he still knows his line," LastO said in a statement.
"It's ironic because I'm sure when he was coming of age, more black folks walked over him...than anyone gay ever did."