Osaka YMCA International School (大阪YMCAインターナショナルスクール, Ōsaka YMCA Intānashonaru Sukūru, OYIS) is an international school in Kita-ku, Osaka, Japan.^[1] Osaka YMCA International School (OYIS) is an English-based, private international school, offering preschool to grade 12. The school year starts in late-August and goes until mid-June–a fall-spring calendar. OYIS began operations in 2001 and received gakko hojin (private school) status from the Osaka prefectural government in 2012. OYIS has a high school program that includes the International Baccalaureate (IB) Diploma Program (DP) which leads to grade 12 graduation. OYIS is currently accredited by the International Baccalaureate Organization (IB) and by the US-based Western Association of Schools and Colleges (WASC).

The school was established in September 2001 from a partnership of Osaka city and the YMCA. In 2002 Alex Stewart of The Journal of the American Chamber of Commerce in Japan wrote that "Osaka city, at least, seems to have woken up to the importance of Osaka YMCA International School."^[2] In June of 2023, OYIS celebrated its first grade 12 graduating class.

As of 2023, OYIS is home to a student population of over 300 students, representing over 30 countries from around the world. William A. Fischel, author of Making the Grade: The Economic Evolution of American School Districts, stated that a version of the OYIS website which had names of students, "at least half of which suggest Japanese parentage", made him conclude that OYIS was not only for North American families.^[3]