No Mercy (2003) was a pay-per-view event produced by World Wrestling Entertainment (WWE) and presented by Subway, which took place on October 19, 2003, at the 1st Mariner Arena in Baltimore, Maryland. It was the sixth event under the WWE No Mercy chronology and starred wrestlers from the SmackDown! brand.
- WWE Heat - Billy Kidman defeated Shannon Moore
- Tajiri (c) defeated Rey Mysterio for the WWE Cruiserweight Championship
- Chris Benoit defeated A-Train by submission
- Zach Gowen defeated Matt Hardy
- The Basham Brothers (Doug Basham and Danny Basham) defeated The APA (Faarooq and Bradshaw)
- Mr. McMahon (with Sable) defeated Stephanie McMahon (with Linda McMahon) - "I Quit" match in which Stephanie could also win by pinfall, and the loser was forced to resign from his/her job.
- Kurt Angle defeated John Cena by submission
- Big Show defeated Eddie Guerrero (c) for the WWE United States Championship
- Brock Lesnar (c) defeated The Undertaker - Biker Chain match for the WWE Championship