The 20-year-old has recently returned to fitness following a cruciate knee ligament injury sustained on loan at Wolves last season and moves to the Valley until New Year's Day.
Frimpong has made two appearances for the Gunners this term, in the Capital One Cup triumphs over Coventry and Reading, and joins the Addicks in search of regular first-team football.
"We're really happy that he's coming in to join our squad, and we welcome him to the club," Charlton manager Chris Powell told the club's official website.
"We've had our eye on him for a while, and with the busy Christmas period to come, I felt it was right to make sure that we are covered in all areas. We hope that does very well for us in the red or black of Charlton."
Source: PA
Source: PA