The 2003–04 UEFA Cup second round was played from 29 October to 11 December 2003. The round consisted of 24 ties, with the winners advancing to the third round of the 2003–04 UEFA Cup.
All match times are CET (), as listed by UEFA.
Draw.
The draw was held on 17 October 2003, 12:00 CEST, at the UEFA headquarters in Nyon, Switzerland. Teams were divided into geographical groups, each with seeded and unseeded pots.
Summary.
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The second round featured the 41 winners of the first round. The first legs were played on 29 October and 6 November, and the second legs were played on 27 November and 11 December 2003.
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Matches.
"Rosenborg won 1–0 on aggregate."
"Gaziantepspor won 6–1 on aggregate."
"2–2 on aggregate; Levski Sofia won on away goals."
"Spartak Moscow won 5–3 on aggregate."
"Dnipro Dnipropetrovsk won 3–1 on aggregate."
"3–3 on aggregate; Brøndby won 3–1 on penalties."
"Auxerre won 4–0 on aggregate."
"0–0 on aggregate; Vålerenga won 4–3 on penalties."
"Bordeaux won 2–1 on aggregate."
"Gençlerbirliği won 4–1 on aggregate."
"Barcelona won 5–0 on aggregate."
"Villarreal won 2–1 on aggregate."
"Liverpool won 2–1 on aggregate."
"1–1 on aggregate; Debrecen won on away goals."
"Mallorca won 3–2 on aggregate."
"Sochaux won 6–2 on aggregate."
"Newcastle United won 4–2 on aggregate."
"Parma won 9–0 on aggregate."
"Teplice won 3–1 on aggregate."
"Perugia won 3–1 on aggregate."
"Roma won 2–1 on aggregate."
"1–1 on aggregate; Groclin Grodzisk Wielkopolski won on away goals."
"Benfica won 5–1 on aggregate."
"Valencia won 4–0 on aggregate."