Glenys Linos (born Glenys Birch on September 29, 1937, in Cairo; died January 30, 2020, in Vienna) was a British-Greek mezzo-soprano opera singer. The daughter of an English father and a Greek mother, she grew up in the United Kingdom, where she also attended school. Linos pursued her music education at the Conservatory of Athens, initially studying the flute before switching to vocal training. She received vocal lessons from the renowned opera singer Elvira de Hidalgo in Milan and later sought vocal advice from Dennis Hall in Bern. Until 1974, she performed under the name Glenys Loulis.

Linos began her singing career in Germany, holding permanent engagements at the Stadttheater Mainz (1968–1969), Stadttheater Ulm (1969–1973), and Staatstheater Wiesbaden (1973–1977). From 1977, she regularly performed at the Zurich Opera House, where she was a permanent ensemble member until 1982 and continued with a permanent guest contract thereafter. Her notable roles in Zurich included Messagera in "L’Orfeo," Gräfin Geschwitz in "Lulu," Charlotte in "Werther," Brangäne in "Tristan und Isolde," Giulietta in "Hoffmanns Erzählungen," and the title role in "Penthesilea." She was particularly acclaimed for her portrayal of Carmen, a role she performed over 200 times at various venues, including the Opéra de Paris, Bavarian State Opera, Deutsche Oper Berlin, and others.

In 1971, Linos appeared at the Bayreuth Festival as Schwertleite in "Die Walküre" and in 1978 at the Munich Opera Festival as the Nurse in "Die Frau ohne Schatten." She also performed at the Staatstheater Wiesbaden as Adriano in "Rienzi" and at the Stadttheater Bern as Santuzza in "Cavalleria rusticana." In 1982, she participated in the Maggio Musicale Fiorentino and later sang Brangäne in concert performances in Bern. Between 1984 and 1986, she performed the role of Storge at the Salzburg Festival in a staged production of the oratorio "Jephtha." Additionally, she appeared at the Opéra National de Paris as Laura in "Der steinerne Gast" during the 1984/85 season.