In 2020，the sudden COVID-19 pandemic triggered a global public crisis. The superposition of the great changes that are unseen in a century and centurial pandemic has pushed the international situation to evolve in the direction of uncertainty and accelerated transformation. Based on the national strategic demands and practical interests，Japan continues to promote the “Indo-Pacific Version”，and its relations with Oceanian countries have demonstrated a trend of “promoting stability through progress as well as responding to changes with stability”. The cooperation between the two sides in the fields of political interaction，economic and trade mutual assistance，defense and security，and people-to-people and cultural exchanges has maintained an accelerated development trend. On the one hand，win-win cooperation is accord with the interests of all parties，Japan aims to develop special partnerships with Oceanian countries；On the other hand，facing complex changes in the geo-strategic situation，Japan continues to deepen its defense cooperative relations with Australia and other countries in an attempt to forge the Oceanian countries as the significant pivots of the “democratic and secure diamond”.