Julia Louis-Dreyfus won the Emmy for lead actress in a comedy series for her role as frazzled Vice President Selina Meyer in HBO's "Veep." Louis-Dreyfus had won the category in 2006 for "The New Adventures of Old Christine."
Louis-Dreyfus, 51, won an Emmy for supporting actress in a comedy in 1996 as Elaine Benes in "Seinfeld."
She has received 13 Emmy nominations for her comedy series work.
Louis-Dreyfus topped a field that included Lena Dunham in "Girls," Melissa McCarthy in "Mike & Molly," Zooey Deschanel in "New Girl," Amy Poehler in "Parks and Recreation," Tina Fey in "30 Rock" and Edie Falco in "Nurse Jackie."
The 64th Primetime Emmy Awards are being handed out at the Nokia Theatre in Los Angeles, and the show is being televised live on ABC.