Utsubo Monogatari (うつほ物語, "The Tale of the Hollow Tree")^{[lower-alpha 1]} is a late 10th century Japanese story. It is Japan's oldest full-length narrative.^[1][2]

The author is unknown. Minamoto no Shitagō is cited as a likely candidate;^[1] however, it may have had multiple authors spanning a number of years.^[2] The text is referenced in a number of later works such as Kagerō Nikki (c. 977), Makura no Sōshi (1002), and Genji Monogatari (c. 1021), suggesting compilation between c. 970 and 999.^[2]

The text is illustrated in an emakimono by Asukabe no Tsunenori, with calligraphy by Ono no Michikaze.^[3]

The title of the story, The Tale of the Hollow Tree, is taken from an incident early in the text. The protagonist Nakatada and his mother flee to the mountains and live in hollow cedar tree.^[1][2] The ateji 宇津保 are also used.^[2]

The story is twenty volumes in length and revolves around a mystical harp that passes through four generations. It belongs to the monogatari genre and is subclassified as a denki monogatari.^[1]

It contains the following chapters:

The story is generally divided into three major sections:^[1][2]

1. Chapters 1-12: Toshikage is sent to China but shipwrecks in Persia. He obtains the mystical harps and returns to Japan. He has a daughter and teaches her music. The daughter has a son, Nakatada, and raises him in hollow tree. Nakatada seeks marriage to Atemiya.
2. Chapters 13-18: Various political rivalries revolving around the Nakatada household and the crown prince.
3. Chapters 19-20: Nakatada passes on the family musical traditions to Inumiya

An English translation by Ziro Uraki was published in 1984 by Shinozaki Shorin under the title The Tale of the Cavern (Utsuho Monogatari) (ISBN 4784104372).^[4]