Williams and Australian favourite Lleyton Hewitt were confirmed as early entries for the season-opening event, one of the key warm-up tournaments ahead of the Australian Open, on Wednesday.
French and US Open champion Williams is the defending champion at the event having beaten Anastasia Pavlyuchenkova in the final back in January.
"I remember I was really excited to win," Williams said. "I was so focused on the final and felt like this was a good start for the Australian Open.
"They have a great fitness centre; they have great courts that are identical to the surface played in Melbourne. Plus I have a week off after the tournament, so it's always a good preparation to play in Brisbane, and it's always fun to go back and try and defend your title."
Hewitt joins a men's field which already includes Roger Federer.
He said: "(There's a) great atmosphere out there and great crowds - they really get behind their tennis in Queensland, and I'm really looking forward to going back for a second year in a row."
Tournament director Cameron Pearson is happy with how his draws are shaping up.
He said: "We are thrilled to welcome back our 2013 champion Serena Williams and Lleyton Hewitt, both players are crowd favourites.
"Serena is one of the most dominant figures of world tennis. Since claiming the Brisbane title this January, Serena has again had a wonderful year on the court which has culminated in her winning her fifth US Open title and second French Open crown.
"Lleyton is one of our country's most accomplished players and has a strong and loyal following here in Queensland. At 20 he was the youngest male ever to be ranked number one in the world, and at age 32 he is still achieving impressive results, and adds star power to our line-up."
The tournament takes place from December 29 to January 5. The Australian Open starts on January 13.