The Addicks will travel to the Broadfield Stadium to meet Blue Square Premier side Crawley on Tuesday, July 21.
Crawley boss Steve Evans said: "Charlton are a big London club and it should be fantastic.
"It should prove to be both a tough match and another great game of football and it will certainly be two teams who like to get the ball down and play."
Charlton will then head to Underhill on Saturday, July 25 to face the League Two Bees in a match agreed when midfielder Dean Sinclair moved to The Valley back in 2007.
Charlton's pre-season build-up is expected to begin with the traditional curtain-raiser against Welling United in early July.