According to "SEN Kakeifu" (genealogy of the SEN family) and "SEN no Rikyu Yuishogaki" (a history of SEN no Rikyu), his grandfather SEN'ami was from the TANAKA clan, a branch family of the NITTA and SATOMI clan, and the grandfather had worked as Doboshu (experts in art) to Yoshimasa ASHIKAGA. It is said that Rikyu took the family name of his grandfather.
「千家系譜」､「千利休由緒書」によると利休の祖父は足利義政の同朋衆だった千阿弥（専阿弥・新田氏里見氏の一族田中氏の出身）といい、その名をとって千姓としたとされている。