After initially working as a primary school teacher in his native Chiba Prefecture, he moved to Tokyo and became a full-time poet.
He published in several prestigious poetry magazines, even helping to found both Araragi and Nikkō, before setting up his own poetic society, the Aogaki-kai, and taking on disciples.
[2] In 1924, he joined Yūgure Maeda, Hakushū Kitahara, Toshiharu Kinoshita, Zenmaro Toki and others in forming a group to publish a new literary magazine, Nikkō, which was to be purely devoted to Modernism.
[2] Other collections of his poetry include Okujō no Tsuchi (屋上の土), Seigyū-shū (青牛集), and Teibon Koizumi Chikashi Zenkashū (定本古泉千樫全歌集).
[2] In 1926 he founded the Aogaki-kai (青垣会) and took on students,[2] but before their poetry journal Aogaki could enter publication Koizumi himself died.