50 Cent is in the clear, for now, for chucking a microphone into the crowd during his L.A. show back in August ... an incident that left a spectator with multiple lacerations to her head and face.
Power 106 radio host Bryhana Monegain filed a police report following the incident on August 30 ... and cops originally presented the case to the L.A. County D.A. as a felony -- but the D.A.'s Office later kicked it to the L.A. City Attorney's office.
Now, the City Attorney's office tells TMZ no criminal charges have been filed against the 48-year-old rapper, and won't be filed as long as he keeps his nose clean.
We're told the case will remain open for 1 year from the date of the incident ... and it could be re-evaluated for possible criminal charges should there be any further incidents between 50 and Bryhana.
This all started when 50 Cent performed at L.A.'s Crypto.com Arena, and video showed him angrily throwing his mic into the crowd ... and it smashed Bryhana in the forehead so badly, she needed medical assistance.
There were technical issues during the concert, and 50 was pissed about the mic malfunctioning. His lawyer Scott Leemon told us 50 would "never intentionally strike anyone with a microphone."