The 2005 Great American Bash was the second annual Great American Bash professional wrestling pay-per-view (PPV) event produced by World Wrestling Entertainment (WWE), and 16th Great American Bash event overall. It was held exclusively for wrestlers from the promotion's SmackDown! brand division. The event took place on July 24, 2005, at the HSBC Arena in Buffalo, New York.

The main event was Batista defending the World Heavyweight Championship against John "Bradshaw" Layfield (JBL). JBL won the match after Batista was disqualified, but did not win the title because a championship can only be won via pinfall or submission. One of the featured matches on the undercard was Rey Mysterio versus Eddie Guerrero, which Mysterio won by pinfall. The other was Orlando Jordan versus Chris Benoit for the WWE United States Championship, which Jordan won, also by pinfall. The event was also notable for the final WWE appearance of Muhammad Hassan, who was involved in a controversial angle on an SmackDown! episode that aired on the same day of the London bombing attacks earlier that month.

The event grossed over US$375,000 in ticket sales from an attendance of 8,000, and received about 233,000 pay-per-view buys, the same amount as the following year's event. This enabled WWE's pay-per-view revenue to increase by $4.7 million from the previous year. When the 2005 event was released on DVD, it reached a peak position of second on Billboard's DVD Sales Chart. The event was also available free of charge for Armed Forces members and their families.