As Obama arrived at the Verizon Center, fans and the players applauded him. Obama chose a corner chair to sit with some old friends from Chicago and shook hands with fans sitting behind him.
The game was delayed slightly as officials waited for his entrance.
The security in the building is incredible, of course. To enter, reporters had to be scanned with a hand wand, walk through a metal detector and have their bags sniffed by bomb-sniffing dogs and hand-inspected by Secret Service agents, the Chicago Tribune's K.C. Johnson reported.
Obama had already welcomed the Bulls into town Thursday, when the team visited him at the White House and presented him with a jersey.
White House senior adviser David Axelrod also attended Friday's game.