Fulfilling his promise kept him in Japan for many years, all the way up to his retirement in 1989, at which time he returned to Taiwan to teach at the National Academy of Arts (now National Taiwan University of Arts). In 1991, he restarted the Fifth Moon Group after more than 20 years of inactivity, and that year they held a commemorative 30-year retrospective exhibit spanning the years 1960 – 1990.
為了信守承諾，郭東榮長居日本，直到 1989 年退休，才返台任教於國立藝專（今國立台灣藝術大學），1991 年重組已中斷二十多年的「五月畫會」，主辦「1960～1990 五月畫會紀念展」。