Kenjirō Tokutomi(徳富 健次郎,Tokuyomi Kenjirō?, December 8, 1868 in Minamata, Japan - September 18, 1927 in Ikaho) was a Japanese writer and philosopher. He was the younger brother of historian Tokutomi Sohō. He wrote novels under the pseudonym of Roka Tokutomi (徳冨 蘆花), many of which were translated into a number of languages including English, French, and German. He corresponded with Leo Tolstoy. A copy of a letter is on display in the small museum located in the Roka Kōshun-en Park, along with belongings.
One of his most famous novels is Hototogisu (English translation: The Cuckoo).
From February 27, 1907 until his death, he lived in a house in Musashino (Setagaya, Tokyo, Japan). At his wife's death the property was donated to the City of Tokyo to be used as a park. It was named Roka Kōshun-en in his honor.