Bruno Mars Sued Over Single 'Uptown Funk'

Bruno Mars and Mark Ronson are under fire for their Grammy winning single, "Uptown Funk" by a rap group who claims the song is just way too similar to their 70s hit.

A female rap trio named The Sequence released the single "Funk You Up" in 1979 ... a hit that was the third rap song ever to reach Billboard's Top 50 Singles. In court docs, obtained by TMZ, the group claims Mars' hit has "significant and substantially similar compositional elements" of "Funk You Up."

Mars and Ronson have faced several lawsuits stemming from the single ... most recently in September.

The Sequence is asking for a jury trial and unspecified amount of money from Mars -- and songwriter Ronson -- who penned the track.