The Greek mezzo-soprano Katerina Roussou was born in Canada and studied singing at the Athens Conservatory of Music and Drama, while at the same time graduated from the National Technical University of Athens in the Department of Electrical Engineering. She received the “Maria Callas Scholarship” as well as a scholarship for the “A. Onassis Foundation” to study at the Royal Academy Opera Course, from which she graduated with the Highest Distinction "DipRAM". She then continued on the postgraduate course at the Academy of Music of Ljubljana with professor Alenka Dernač-Bunta.

In November 2015 she made her debut at the Greek National Opera in their children's opera "Carmencitas"  based on the opera Carmen by G. Bizet, and sung the title role. 

On the operatic stage she has sung the role of Marcellina in Mozart’s “Le nozze di Figaro” at the ETA-Hoffmann theatre in Bamberg, one of the 6 girls of Mahagonny in Kurt Weill’s “The rise and fall of the city of Mahagonny” at the Athens Megaron (production: La Fura dels Baus), the Third Lady in Mozart’s “Magic flute” (British Youth Opera - Peacock Theatre, London) and has performed one of the Flowermaidens in Wagner’s “Parsifal” for the London Wagner Society. Her operatic experience also includes the roles of Cherubino and Marcellina in Mozart’s “Le nozze di Figaro”, Vava in Shoshtakovich’s “Cheryomushki”, Il Destino and Furia II in Cavalli’s “La Callisto” and Angelina in Rossini's "La Cenerentola".

As a soloist she has sung with the Athens State Orchestra, the Symphonic Orchestra of the Greek Radio, the Symphonic Orchestra of the Athens Municipality, the Ljubljana Philharmonic Orchestra, the Ingolstadt Chamber Orchestra, in works such as Mozart’s “Requiem”, Mahler’s “2nd Symphony”, Hatzidakis’ “Ornithes” and D. Papadimitriou “Kavafis”. She has sung with the International Bachakademie under Helmut Rilling in Greece and Germany. In April 2010 she sang in a gala benefit concert at the Athens Megaron with world famous tenor Jose Cura.

She has worked closely with actress Magda Mavrogianni in a series of musical-theatrical performances about the lives of famous women: Frida Kahlo, Martha Freud, Clara Schumann, Carmen, the Duchess of Piacenza, performing them around Greece.

She has given a number of recitals in Greece and abroad (Spain, UK, Slovenia, France, Croatia, Sweden) and has participated in many festivals. She has also sung in many oratorios. 

She has recorded excerpts from Mozart’s “Le nozze di Figaro” (Marcellina) for BBC Radio3, 5 songs by Markos Dragoumis for the literary magazine “Nea Synteleia” and 2 songs on poems by Giorgos Karter for the State Radio of Thessaloniki. Together with the famous soprano Sonia Theodoridou, she has recorded the second CD of Athanasios Simoglou’s songs on poems by the Greek poet K. Kavafis (Orchestra Mobile, cond: Theodoros Orfanidis).

She has participated in the film "Our Callas" about the life of Maria Callas, by the Swedish-Greek director Babis Tsokas.

In 2015, together with pianist Johan Sandback and violinist Matoula Zachariadou, they started the association Grekisk Konstmusik i Sverige to promote the Greek culture by presenting the rich repertoire of Greek Classical Music to a wide public in Sweden. The association organises among others the Greek Classical Music Festival at the Musikaliska.