Yoshiko Iwai was born in Nagoya, Japan. At the age of 13 she won the West Japan Youth Music Competition. She studied with Prof. Hitoshi Kobayashi at Tokyo National University of Fine Arts and Music (Tokyo Geijutsu Daigaku). During this time she won 2nd prize at the 52nd Japanese National Music Competition.

In 1987 Yoshiko Iwai moved to Germany to further her studies with Prof. Friedrich Wilhelm Schnurr at the Hochschule für Musik in Detmold and  graduated in 1993 with highest honour (Konzertexamen). She also participated in masterclasses held by Prof. Gyorgy Sebok. From 1993 to 1996 she taught at the Hochschule für Musik in Detmold.

Yoshiko Iwai has been awarded many major prizes at international music competitions. She was a finalist in the 14th Clara Haskil Competition (Vevey, Switzerland), received second prize an numerous awards at the 3rd European Chopin Piano Competition Darmstadt 1989 and won first prize (Felix Mendelssohn-Bartholdy Prize) at the Mendelssohn Competition Berlin 1991. In addition she won second prize at the International Geza Anda Competition (Zürich, Switzerland 1994).

She recorded several CDs (Mozart piano pieces, Clara Schumann piano works and Paul Juon chamber music etc.) and participated in numerous broadcasting-productions.

Yoshiko Iwai lives in Zürich and performes frequently in Japan, Switzerland and many other European countries.

Since 2000 she works at the Zurich University of the Arts (Zürcher Hochschule der Künste).