Young Lions to play at The ValleyTweets by @MillwallFC
Ticket prices are £5 adults and U18s £1 if accompanied by a full paying adult.
The tie between The Lions and Addicks will be settled on the night, meaning that extra-time and penalties will be required if the game is level after 90 minutes.
Charlton were handed a bye into Round Three, but exited the competition at this stage last season when Cardiff City recorded a 1-0 victory in SE7.
The Lions saw off Dover Athletic (2-0) in Round One before comfortably beating Woodbridge Town by a 9-1 score in the Second Round at The Den last week.
Millwall's FA Youth Cup Third Round tie against Charlton will be played at The Valley on Wednesday 2nd December (7pm).