Tokyo native, Kojiro Tsuchiya, graduated from Tokyo National University of Fine Arts and Music in vocal music and acquired his Master's degree in solo voice from the same school. While in graduate school, he simultaneously completed studies of opera performance practice as a research student in Nikikai Opera Studio and in masterclasses, and earned a prize for excellence. He later traveled abroad as a Rotary Scholar in Piacenza, Italy, and studied the musical and vocal performing techniques of La Scala coach, Luciano Berengo, and soprano, Alda Morgan. Tsuchiya received favorable acclaim at the Asola Music Festival, and went on to perform various operas and concerts in Milan, Mantua, Verona, and Levico.

Tsuchiya made his operatic debut in a performance of Menotti's work "The Telephone" while attending university. He subsequently appeared many times in the fitting title role of the Marriage of Figaro, and participated in new productions such as a narration opera by master storyteller, Kurenai Kanda. Works performed thus far include Die Zauberflöte (Papageno, Man in Armor), Cosí Fan Tutte (Alfonso, Guglielmo), Don Giovanni (Don Giovanni, Leporello), Le Nozze di Figaro (Conte), La Traviata (Germont), La Bohème (Marcello), Madama Butterfly (Sharpless), Carmen (Escamillo), Pagliacci (Sylvio), Cavalleria Rusticana (Alfio), Gianni Schicchi (Marco / a production with kyogen master, Mannojo Nomura), Un Ballo in Maschera (Silvano), Tannhäuser (Biterolf), Hamlet (Horatio), Die Schweigsame Frau (Morbio / a Japan premiere), Das Liebesverbot (Angelo), Visa for 6000 People (Senji, cover), and others such as the chamber opera Die Kluge (Man with the Mule), La Serva Padrona (Uberto), Amahl and the Night Visitors (King Melchior), The Old Maid and the Thief (Bob), Kappatan (Kappa), Amanjaku and Urikohime (Jissa), and many other productions with opera organizations including the New National Theater, Nikikai, Tokyo Opera Produce, Tokyo Chamber Opera Theatre, and Nissay Theatre.

As a concert soloist, he has given performances of Beethoven's Ninth Symphony, Carmina Burana, the religious music of Bach's St. Matthew Passion (Jesus, Pilate) and other cantatas under the direction of St. Thomas Church cantor Hans-Joachim Rotzsch, and other works such as Mozart's Requiem, Four Seasons, and Creation. In addition to annual theme-based solo recitals, Tsuchiya has often collaborated with Kirov Opera principal soprano, Elena Mirtova, in joint concerts, and many other artists both here and abroad. Not being limited to classical works, he starred in the musical "Ennin" broadcast on NHK, collaborated with pop singer Emiko Shiratori, has concertized in a wide range of genres e.g., jazz and tango, and formed a trio for bass and violin called "Remembrance".

- Agency for Cultural Affairs 2000 Internship
- Japanese Singing Association Academy Member
- Nikikai Member