In 1988, Katanec joined VfB Stuttgart in the German Bundesliga. The club reached the 1989 UEFA Cup Final, but lost to Diego Maradona's Napoli. Katanec played just one season for Stuttgart. In 1989, he signed for Italian Serie A side Sampdoria, where he won the European Cup Winners' Cup in his first season. In 1991, Sampdoria won the "Scudetto" as Serie A champions, while the next year, the club reached the 1992 European Cup Final, losing to Barcelona. In 1994, he also won the Coppa Italia with Sampdoria under manager Sven-Göran Eriksson.