"The appeal that was submitted to the NCAA was denied," a Florida spokesman said in a statement Friday night.
Grierwas suspended in October after testing positive for performance-enhancing drugs.
Attorneys representing Grier argued the appeal Monday in a conference call with Florida athletic director Jeremy Foley and the NCAA.
Grier's suspension was handed down Oct. 12. The positive test carries an automatic suspension of one calendar year from the NCAA, which means the redshirt freshman will not be eligible to return until Florida's seventh game of the 2016 season, againstMissourion Oct. 15.
Grier said in a news conference last month that the positive testwas the result of something he took over the counter and did not get approved by Florida trainers.
But Grier had been a breath of fresh air for Florida before his suspension.
He became the first Gators quarterback since Tim Tebow in 2009 to pass for more than 200 yards in three consecutive games.
Grier's completion percentage, passing yards per game and TD-to-interception ratio also were the best by a Gator since 2009. His completion percentage (65.8) and scramble yards (154) ranked first in the SEC.
Information from ESPN's Brett McMurphy was used in this report.