CHRIS BROWN CHARGE HAS REDUCED TO MISDEMEANOR ASSAULT

Chris Brown just got cut a big break ... the assault charge has just been reduced from a FELONY to a MISDEMEANOR ... and Chris pled not guilty.  Chris has just been released without bail. He's also required to stay 100 yards away from the victim.

Chris had been ordered to take a drug test, but the judge just vacated that order.  It's standard in such cases to order a drug test, but that has been cancelled. 

The bodyguard's charge was also reduced to a misdemeanor.

TMZ broke the story ... Brown was arrested for felony assault early Sunday morning in Washington D.C. after allegedly attacking a man outside a hotel and breaking his nose.

Brown allegedly got into an argument with a man, said "I'm not down with that gay s**t, I'm into boxing," and then punched him in the nose.

Law enforcement sources Reveals That... the fight started when the man and his friend photobombed Chris, who was posing for a picture with two girls.

Sources close to Chris insist the fight wasn't over a photo -- they say the alleged victim tried to force his way onto Chris' tour bus, and Chris was merely trying to stop a trespass.

Brown has been in custody since the incident.