The tenor Naoyuki Okada was born in 1978, in Tokyo, where he began studies of singing at the age of sixteen.
Okada attended the Tokyo National University of Fine Arts and Music and studied German Lieder with the tenor Uwe Heilmann. He graduated with the Master of Music degree, studying operatic repertoire with the soprano Marcella Reale.

After the completing his studies in university, Okada became a member of New National Theatre Tokyo Young Artists Training Programme and made his operatic debut as Rinuccio in Gianni Schicchi.
During the third year of the programme, he went to Bologna, Italy and studied at Reale Accademia Filarmonica di Bologna with the tenor Sergio Bertocchi and the pianist Paola Molinari.

In 2006 he won a scholarship from Japanese government and returned to Bologna to continue his work with Bertocchi and Molinari.
In 2008 Okada, as the winner of the Japanese national audition, debuted professionally in the role of Pinkerton in Madama Butterfly at the municipal theatre in Kagawa, Japan, performing with the conductor Yoshinori Kikuchi and the soprano Yasuko Hayashi as Butterfly, both of whom had great success at the Teatro alla Scala.
In 2011 winning a huge competition he became a member of the "Ensemble Opera Studio" of the Teatro Carlo Felice in Genoa where he made his international debut as Rinuccio in Gianni Schicchi and as Priester/Geharnischtermann in Die Zauberflöte. In season of 2011/2012 at the Teatro Carlo Felice, he also interpreted, as the unique foreign cast, the role of Scipio Premuda in the contemporary opera composed by Marco Betta Che fine ha fatto la piccola Irene? with spoken dialogues in Italian.
He appears continually on the stage of the Teatro Carlo Felice in almost every operatic seasons until the present; Roderigo in Otello, Maintop in Billy Budd, Loris Ipanov in Fedora (in dress rehearsal opened for public), and Gabriele Adorno in Simon Boccanegra.
At the same time Okada appears also on the Japanese stages: Alfredo in La Traviata, Rodolfo in La Bohème, Turiddu in Cavalleria Rusticana, Calàf in Turandot, Luigi in Il Tabarro, Maurizio in Adriana Lecouvreur, and the title role in Andrea Chénier.
In 2013 held his first Liederabend in Tokyo.

The elegance of the voice and high musicality of his singing are highly appreciated by experts and the public. Okada is also recognised as a tenor with beautiful diction in many languages, not only in his singing but also in spoken dialogue.