Hewitt, who had beaten Federer just once in 17 ATP meetings since 2002, came away a 6-1, 4-6, 6-3 winner Sunday in claiming the tournament in his home country. It was the 29th ATP championship for Hewitt, who collected his first exactly 16 years ago at Adelaide, Australia.
His most recent tournament win before Sunday was in 2010 in Halle, Germany, when he beat Federer 3-6, 7-6 (7-4), 6-4 in the final.
Federer entered the Sunday final without having his serve broken in his first three matches in Brisbane but Hewitt posted three first-set breaks and didn't face a break point in taking the lead.
Federer had the only break of the second set to even the match and Hewitt went ahead in the third set with a fourth-game break and held out from there -- saving seven break points -- for the win.
"I played great obviously at the start, really well," Hewitt said. "It took Roger a little bit of time to get into the match. Then I just had to fight hard at the start of the third set."
Hewitt won $82,040 along with the title, pushing his career winnings past the $20 million mark. Federer picked up $43,210 to add to his ATP-record winnings of nearly $79.3 million.