A vandal spray painted "This is Racist" on the Confederate soldier memorial.
The vandalism was noticed by a staff member on Monday morning.
The sheriff's department is reviewing security cameras from the area to see if the vandal was caught on video.
The statue was commissioned in 1918 by the Daughters of the Confederacy.
Confederate statues and memorials have been protested recently by activists who want Confederate symbols removed from public display.
Peggy Riddle, Director of Denton County Museums, put on rubber gloves and used a bucket of mild chemicals to begin the careful process of removing the graffiti.
Only a Vague red outline remained by Monday afternoon.
Denton County Judge Mary Horne told FOX 4 what the monument means to her.
“I've got a lot of friends that were killed in the Vietnam War,” said Horne. “We have the Vietnam War Memorial in Washington, DC. There's an awful lot of people who disagree with the war in Vietnam, but I sure don't think we should be taking down the Vietnam War Memorial. It's to honor the soldiers who served their country.”
Horne says they've stepped up security at the courthouse -- not because of vandalism, but because of other recent criminal mischief in the area.