1/18/23 -- Ice Spice's attorney, Leon Morabia, tells TMZ …“The claim is baseless. We will vigorously defend this case and look forward to our day in court when we will be fully vindicated.”

Ice Spice is being dragged to court over her hit song "In Ha Mood" ... 'cause a rapper and his producer are accusing her of straight up ripping off their work.

Ice Spice is being sued for copyright infringement by D.Chamberz, who says he wrote, recorded and released a song called "In That Mood" a year before her famous single.

According to the lawsuit, obtained by TMZ, D.Chamberz says he released his song on all major digital platforms in January 2022 and he thinks Ice Spice's producer heard it on the radio way before her song came out.

He claims Ice Spice's song copies the beat, lyrics, hook, rhythmic structure, metrical placement, and narrative context of his track.

As for how "In That Mood" allegedly appeared on Ice Spice's radar ... D.Chamberz claims he performed it dozens of times in NYC in venues near where Ice and her producer, Riot, reside.

D.Chamberz also says his song got airplay on Hot 97 FM in NYC, and he thinks it's more likely than not Riot was tuning in ... and he says there are social media receipts backing his claim.

Ice Spice's song is certified gold and the music video has more than 45 million views on YouTube ... and D.Chamberz wants at least half of the song's publishing and other revenue ... plus damages.

We reached out to Ice Spice's camp ... so far no word back.