Bush lamented the Republican Party's rocky relations with blacks. He pledged to improve that relationship and work with the NAACP's new leader to achieve common goals.
That line generated boisterous applause and cheers from the audience, which generally gave the president a polite, reserved reception.
Black support for Republicans in elections has hovered around 10 percent for more than a decade. In 2004, Bush drew 11 percent of the black vote against Democrat John Kerry.
Most of the president's talk generated a smattering of applause. But many in the convention center stood and clapped when he urged the Senate to renew a landmark civil rights law passed in the 1960s to end racist voting practices, such as poll taxes and literacy tests, in Southern states.
The Senate passed the bill later Thursday and sent it to the White House, according to the AP.
According to AP-Ipsos polling conducted in June and July, 86 percent of blacks disapprove of the way Bush is handling his job, compared with 56 percent of whites who disapprove.