#4The Ultimate Warrior (never lost: 5-0)
The Ultimate Warrior was a mainstay at WWE SummerSlam during 1988-92 and won five consecutive matches at the event over those five years. He put down The Honky Tonk Man and Rick Rude in 1988 and 1989, respectively, with both contests scheduled for the Intercontinental title. In 1990, he defeated Rude in a WWE title bout, this time inside a steel cage.
The next year, Warrior teamed up with Hulk Hogan to defeat General Adnan, Colonel Mustafa, & Sergeant Slaughter in a Handicap match. In his final appearance at SummerSlam, Warrior scored a victory over Randy Savage via count-out.
#3 Booker T (never won: 0-5)
Despite being one of the most decorated Champions in all of pro-wrestling, Booker T hasn't had much luck at SummerSlam. Soon after he made his way to WWE in 2001, Booker T lost a WCW title match to The Rock at SummerSlam. Booker and Goldust lost a Tag Team titles match to The Un-Americans at SummerSlam 2002.
Two years later, Booker lost the first of a "Best of 5" series to John Cena. In 2006, Booker T (now King Booker) lost a singles match to Batista, via DQ. At SummerSlam 2007, King Booker lost to a returning Triple H, who had been out of action for the past several months.