Lauryn Hill just pled guilty to a major federal crime ... admitting she intentionally failed to file several tax returns in the past decade -- and now the former Fugees singer faces 3 years in prison.
Hill pled guilty today to three counts of failure to file tax returns for the years 2005, 2006, and 2007 -- when she earned more than $1.8 million.
When the judge asked if Hill "intentionally and willingly" failed to file the returns, she replied, "Yes."
In addition to the 3 years behind bars, Hill could be smacked with $75,000 in fines.
Hill was released on $150,000 bail. Her sentencing hearing is set for November.