The Lions' record goalscorer suffered a knee injury against Walsall last weekend which forced him to miss Tuesday night's win at Carlisle.
However, the problem is only an impact injury and Harris has a good chance of being ready to face the Addicks.
The only other player in the treatment room is Harris' fellow striker Gary Alexander, who is continuing his recovery from a heel operation.
Alexander, who has been on the sidelines in October, has begun light jogging as he attempts to make a comeback before the end of the season.
Charlton's last competitive visit to The Den was back in 1995 while the sides fought out a thrilling 4-4 draw at The Valley earlier this term.