Megan Buckland added 13 points for the Tar Heels, who improve to 7-0 in the Preseason WNIT after winning the tournament in 2008.
Despite holding the Hoyas to 20.5 percent (8 of 39) shooting in the first half, UNC (3-0) led just 26-22 at intermission. But the Tar Heels opened the second half with a 10-4 run to go up 36-26, and Georgetown would not get any closer than eight the rest of the way. Roundtree scored the first five points of the run.
UNC held Georgetown (2-1) to 23.5 percent (16 of 68) from the field and outrebounded the Hoyas 53-42.
Sugar Rodgers, who entered the game averaging 28 points, finished with 22 points but shot just 6 of 24 field goal attempts. She became the school’s all-time leading scorer with 1,886 points passing Kris Witfil, who finished with 1,885.