O.J. Simpson -- Another Day, Another Tax Lien

IN THE YEAR 2000 ... O.J. Simpson failed to pay over $300k in taxes to the State of California ... this according to a new lien filed against him.

According to docs recently filed by the State of CA Franchise Tax Board ... Simpson -- who is currently rotting away in a Nevada prison for Robbery -- still owes $318,566.04 in unpaid taxes from the Millennium.

TMZ broke the story ... O.J. is knee deep in financial trouble -- he has a federal lien filed against him for the years 2007-2010, for $179,435.07. Not to mention he still owes MILLIONS to the families of Nicole Brown Simpson and Ronald Goldman ... for causing their death.

On that note ... take it away Conan ...