His grandfather, Count Yoshii Tomosane was a former samurai retainer of Satsuma Domain, and member of the House of Peers, the Privy Council and official in the Imperial Household Ministry.

[1] Yoshii left Myōjō to form a new group, Pan no Kai, together with Kitahara Hakushu due to their shared attraction of romanticism and aestheticism.

[1] In 1910, Yoshii published his first tanka anthology, Sakehogai, (Revelry) describing the joys and sorrows of a young poet given to wine and women.

In the same year, he released scripts for radio dramas, such as Saigo no Seppun (The Last Kiss), Gekijo Iriguchi no Hanjikan (Half an Hour at the Theater Door), and Kamome no Shigai (Dead Seagull).

In 1927, his play Ame no Yobanashi (Night Stories in the Rain) about a melancholic traveling performer wandering around the country was broadcast as a radio drama.