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.[1]
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.[2]
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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2–2 on aggregate. Levski Sofia won on away goals.----1–1 on aggregate. Groclin won on away goals.----Dnipro Dnipropetrovsk won 3–1 on aggregate.----1–1 on aggregate. Debrecen won on away goals.----Villarreal won 2–1 on aggregate.----Teplice won 3–1 on aggregate.----Parma won 9–0 on aggregate.----3–3 on aggregate. Brøndby won 3–1 on penalty shootout.----Gaziantepspor won 6–1 on aggregate.----Rosenborg won 1–0 on aggregate.----Spartak Moscow won 5–3 on aggregate.----Perugia won 3–1 on aggregate.----Benfica won 5–1 on aggregate.----0–0 on aggregate. Vålerenga won 4–3 on penalty shootout.----Sochaux won 6–2 on aggregate.----Auxerre won 4–0 on aggregate.----Newcastle United won 4–2 on aggregate.----Roma won 2–1 on aggregate.----Bordeaux won 2–1 on aggregate.----Liverpool won 2–1 on aggregate.----Mallorca won 3–2 on aggregate.----Barcelona won 5–0 on aggregate.----Gençlerbirliği won 4–1 on aggregate.----Valencia won 4–0 on aggregate.