Japan–Tonga relations

Japan and Tonga have maintained official diplomatic relations since July 1970. Japan is Tonga's leading donor in the field of technical aid. The Japanese government describes its relations with Tonga as "excellent", and states that "the Imperial family of Japan and the Royal family of Tonga have developed a cordial and personal relationship over the years". Japan is one of only four countries to have an embassy in Nuku'alofa, whilst Tonga has an embassy in Tokyo.

In early 2009, Japan became the fourth country to establish an embassy in Tonga (following Australia, New Zealand and the People's Republic of China). In March, Ambassador Yasuo Takase became the first resident ambassador of Japan in Tonga. He was also the first resident Japanese ambassador in any Polynesian country.

The opening of the embassy came in a context of increased Japanese development aid in the Pacific.