In January 1996, Ramelow moved to the Bundesliga with Bayer Leverkusen, being a major part of the squads that never finished lower than fourth until the 2003–04 season (except for 2002–03, where they would rank only 15th, the last place before the relegation zone); a defensive-minded player, he scored twice in his top flight debut, a 2–0 home win against F.C. Hansa Rostock on 19 March, and contributed with 16 matches (15 complete) in Bayer's 2001–02 UEFA Champions League runner-up run, including the final loss against Real Madrid.