Mariah Carey is bein' taken to court once again over her classic Christmas hit ... by the 2 men who claim they wrote a song of the same name.

Andy Stone and Troy Powers are coming after Mariah for at least $20 million in damages over her song, "All I Want For Christmas Is You" -- which happens to be the name of their 1989 holiday song.

TMZ broke the story, the refiling is nearly identical to last year's suit -- in which Stone called out Mariah for allegedly copying their track after their song got extensive airplay and even made it on the Billboard charts in the 1993 Christmas season.

In the new docs, obtained by TMZ, Stone and Powers claim there are substantial similarities in the lyrical hook, melody, and overall feel compared to their OG song ... adding Mariah's "palmed off these works with her incredulous origin story, as if those works were her own."

Gotta admit, it's hard to avoid Mariah's catchy tune when November rolls around ... Stone and Powers are looking for the big paycheck and are asking the judge to shut her down nonetheless.