Preston, who won 1-0 at Leicester in the week, were paying their first visit to The Valley for 30 years and they thoroughly deserved the points against a Charlton side, who have completely lost their way in recent weeks.
With only four victories in their last 15 league matches, the Addicks could now miss out in the promotion battle at the top of the table.
But this win helps Preston move further away from the relegation zone and they were always the better side against a Charlton team who gave one of their most abject performances of the season.
Charlton winger Lloyd Sam went off injured after just 13 minutes and two minutes later, Preston took the lead when Chris Brown volleyed home after an excellent defence-splitting pass from Darren Carter.
Charlton rarely threatened the Preston goal in a disjointed display and they continued to struggle after the break.
Indeed, their first effort on goal came from Leroy Lita after 72 minutes, but the on-loan Reading striker fired wide.
But against the run of the play, Charlton scrambled an equaliser on 74 minutes when Matt Holland's cross was toe-poked home by defender Paddy McCarthy.
However within two minutes, the visitors had regained the lead with Brown again the scorer after the Charlton defence had failed to clear a left-wing cross.
In the dying minutes a Darren Ambrose free-kick was about the first meaningful effort that Preston goalkeeper Andy Lonergan had to deal with as the home side were booed off the field as they slumped to their sixth home defeat of the season.