Orfeo 55 was a chamber orchestra founded by conductor and contralto Nathalie Stutzmann. The group gained fame for accompanying performances and recordings in which Stutzmann both sang and conducted. She also led Orfeo 55 purely as a conductor in a range of repertory that expanded beyond the ensemble's original focus on Baroque music.

Stutzmann founded Orfeo 55 in 2009 and remained its artistic director over its entire existence. The orchestra was flexible in size, enabling it to perform repertory ranging from Baroque works for a small chamber orchestra to substantial pieces by Richard Strauss, Tchaikovsky, and Schoenberg. The players were selected not only for their ability as individual performers but for their skill in ensemble playing, and the group used both historical and modern instruments. The orchestra succeeded from the start, attracting bookings in most major European capitals and touring Japan and the U.S. during the 2012-2013 season. Many of Orfeo 55's concerts were purely instrumental, but the greatest novelty in the group's presentation was that Stutzmann often sang and conducted simultaneously. A Vivaldi program entitled Prima Donna went on tour and demonstrated Stutzmann's and the orchestra's abilities. Orfeo 55 served for a time as orchestra-in-residence at the Metz Arsenal Concert Hall. Orfeo 55 attracted support from France's Ministry of Culture, but finances proved a problem, and it disbanded in 2019 due to a lack of funds.

Orfeo 55 recorded five albums. A recording based on the Prima Donna program and a Bach album called Une cantate imaginaire appeared on the Deutsche Grammophon label. For the Warner/Erato conglomerate, Orfeo 55 and Stutzmann recorded Handel: Heroes from the Shadows, Quella Fiamma, and Contralto; the last of these, again with Stutzmann conducting and singing a variety of Handelian roles, appeared in 2021. ~ James Manheim, Rovi