Latics pick up point at the Valley
Peter Clarke's 82nd-minute strike saw the latics draw level and pick up a point at the Valley.
Josh Magennis' first-half strike looked to have given Charlton their first three-point haul since 20 August, but they were dealt a late blow for the second home match in a row.
Charlton's opener came in the 22nd minute when Ricky Holmes powered his way into the box to lay the ball off to Magennis, who blasted it past Connor Ripley.
The Londoners could have doubled their lead before the hour mark, but Magennis curled the ball over the bar after good footwork.
Oldham's equaliser came when Paul Green's lofted free-kick was met by Clarke who headed past Declan Rudd to send the 120-plus travelling fans home happy.
The Latics held on for the point despite suffering a scare when substitute Ademola Lookman struck the bar with five minutes remaining.