Graduated from the special course of the Department of Philosophy of the Imperial University of Tokyo in 1908. He taught at Kanda Koto Jogakko and Tokyo Joshi Taiso Ongaku Gakko (Tokyo Women's School of Gymnastics and Music). After resigning from the post, he opened Iwanami Shoten to mainly deal with old and used books in 1913. He published "Kokoro" by Soseki Natsume the following year and moved into the publishing business. In addition to publishing the "Tetsugaku Sosho" and "Soseki Zenshu", he launched Iwanami Bunko aimed at the popularization of the greatest books worth being called as the world and Japanese classics and Iwanami Shinsho aimed to provide a global perspective and scientific knowledge based on the principle of newly written material. He created a publishing culture called "Iwanami culture". He was prosecuted for the publication of a book by Sokichi Tsuda in 1940, but was acquitted in 1944. As a large tax payer, he was selected as a member of the House of Peers in 1945 and awarded the Order of Culture in 1946.