- Was the first son of the famous sculptor Takamura Kōun (1852-1934).
- Takamura Kōtarō trained as a sculpturer under his father, before joining the Tokyo University of Fine Arts.
- After graduating in 1902, he went abroad to further complete his studies: first in New York, then London and finally in Paris.
- In Paris, he saw The Thinker by the sculptor Auguste Rodin for the first time; Takamura's response to this work was so intense he claimed that he could never look at art the same way again. He began to experiment with his own style, adopting a new approach to both his sculptures and his poetry.
- He was also a translator and writer of many books and articles on Rodin's artistic career, and realized many tributes to the french artist. 
- When he returned from Europe, he was estranged from his family; and entered upon a decadent lifestyle, vigorously opposing social conventions of every kind. 
- He joined a poetry circle called Shinshisha (New Poetry Society), publishing his works to the literary magazine Subaru.
- In 1910 he published Midori iro no taiyô (Green Sun), an essay in wich he argued for the right of an artist to absolute freedom of self-expression; Midori iro no taiyô is still considered as one of the most influential "art-critical" texts in the country.
- Takamura joined Pan no Kai (Society of Pan), the literary group founded by Yoshii Isamu and Kitahara Hakushuu.
- He frequently drank with other Pan no Kai members, but he was also know to abandon such meetings halfway.
After a particular meeting broke up one night in 1910, he drunkenly went to observe some of the girls in the red-light district. He was attracted by the hair style and features of one girl in particular, whom he sketched on a pad that he kept in the breast of his kimono.
- In 1911 he met Nagamuna Chieko (1886-1938) another painter and a member of Seitō-sha, a group for women's liberation. Takamura shared her anti-conformist and progressive aspirations, and the two got married in December 1914.
- The same year, he published his first poetry book Dōtei (Journey).
- In 1912 he founded the Fusain-Kai with other painters and sculptors of the time; the first and only exhibition was held in the Ginza at the Yomiuri Shinbun building and displayed the artists interpretations of various styles associated with European post-impressionism.
- He and Kusano Shinpei were the first critics to take notice of Miyazawa Kenji's self -pulished books in 1924, both of them admired his writing and they introduced him to the literary world, pushing for a wider acknowledgement of his children stories.
- In 1941 he published the book Chiekoshō, a collection of romantic poetry that he wrote about his life with Chieko, who was diagnosed with schizophrenia in 1931 and died of tuberculosis in 1938.
- A movie based on Chiekoshō was made in 1967, and got nominated for the Academy Award for Best International Feature Film.
- In 1951 Takamura received the 2nd Yomiuri Prize.
- Takamura retired from public life during the war; as a self recluse he began making wood carving of animals and wrote the poetry collection A Brief History of Imbecility.
- He died at age 73 due to pulmonary tuberculosis.
- Takamura Koun and Takamura Kotaro: On being a Sculptor, Christine Guth, 2004
- Paris in Japan: The Japanese encounter with European painting, J. Thomas Rimer, Gerald D. Bolas, Takashina Shuji, 1987
- The Singing Heart: An Anthology of Japanese Poems, Kenkichi Yamamoto, 2006
- Being Modern in Japan: Culture and Society from the 1910s to the 1930s, Elise K. Tipton and John Clark, 2000
- MAVO: Japanese Artists and the Avant-Garde, 1905-1931, Gennifer Weisenfeld, 2001
- Kodansha Encyclopedia of Japan Gen Itasaka, 1983
- A Brief History of Imbecility: Poetry and Prose of Takamura Kōtarō, Hiroaki Sato, 1992