Stjepan Hauser, known professionally as HAUSER, is a Croatian cellist. He was a member of 2CELLOS, along with Luka Šulić, and continues to perform solo.

2Cellos were a Croatian cellist duo, consisting of classically trained cellists Luka Šulić and Stjepan Hauser. Signed to Sony Masterworks in 2011, they released six albums. The duo played instrumental arrangements for cellos of well-known pop and rock songs, as well as classical and film music. The duo performed internationally and were featured on several American television series including Glee and The Bachelor. They continue to be active as solo performers.