Tanegashima Tokitsugu served as a bushō during the Sengoku period.  He was a retainer of the Shimazu clan of Satsuma Province.  Tokitsugu served as the fifteenth head of the Tanegashima clan.

In 1556, Tokitsugu was born as the eldest son of Tanegashima Tokitaka, the fourteenth head of the Tanegashima clan.

His father, Tokitaka, received as his formal wife the daughter of Shimazu Tadayoshi, a sengoku daimyō in Satsuma, but together the couple only had daughters and for a long time were not blessed with a son to be the lineal heir to the family.  As a result, Tokitaka received the daughter of Nejime Takashige as a consort who bore Tokitsugu.  At the time, however, the Nejime clan were in conflict with the Shimazu clan so Tokitaka’s act was regarded as nothing other than a betrayal of the Shimazu.  Tokitaka’s formal wife became upset and the couple divorced.

In 1560, Tokitsugu attended his coming-of-age ceremony and adopted the name of Sahyōei-no-jō Tokitsugu.  At the time, he was merely five years old and, in the Sengoku period, it was extraordinarily rare to succeed one’s living father to the headship of the clan at such an early age.

Nevertheless, two years later, in 1562, Tokitsugu died early.  At the time, Tokitaka did not have any other sons to inherit the clan so he reverted to his previous position.  Meanwhile, troubled relations with the Shimazu clan improved after his second daughter became a second wife of Shimazu Yoshihisa.  Later, Tokitaka was succeeded by his second son, Tanegashima Hisatoki.