The Gallup organization said polling June 1-4 indicates 49 percent of Americans view the former president as favorable compared to 46 percent who indicated an unfavorable view.
Bush left office in January 2009 with 40 percent of Americans viewing him favorably and 59 percent unfavorably, Gallup said.
After the Sept. 11, 2001, terrorist attacks, 87 percent of Americans reported a favorable rating of President Bush.
His lowest favorable rating of 32 percent was registered in April 2008 with the economy in recession and gas prices headed toward record highs.
Gallup's June polling was based on telephone interviews of 1,529 adults living in all 50 U.S. states and the District of Columbia.
It carries a margin of error of 3 percentage points.