Japan's government is preparing a revision to the Imperial Household Law that would allow the adoption of men over 15 from former aristocratic branch families to shore up the thinning line of succession, with Prime Minister Sanae Takaichi planning to introduce the bill to parliament before the session ends on July 17. The reform, backed by a consensus among seven political parties, would not grant imperial rank to the adopted men themselves but would extend eligibility to their male descendants.
The imperial household has shrunk to just 16 members, down from 21 in 1989, leaving only three men in the direct line of succession: Crown Prince Fumihito, 60, his 19-year-old son Hisahito, and 90-year-old Prince Hitachi. Princess Aiko, Emperor Naruhito's only child, remains excluded from the throne. Under the proposal, women who marry out of the family could choose to retain their imperial status.
The move has drawn skepticism. Multiple candidates from former branch families have declined adoption, and experts have called instead for allowing women to ascend the throne — a position shared by 72 percent of Japanese respondents in a May 2026 Asahi poll.