Hiroko Nagata (?? ??, Nagata Hiroko, 8 February 1945 – 5 February 2011), sometimes mistakenly referred to as Yoko Nagata, was a Japanese leftist revolutionary and terrorist who was convicted of murder and sentenced to death in Japan.
Nagata was convicted of murdering, or participating in the murder of, fellow members of the United Red Army (URA) during a group purge in Gunma prefecture, Japan in February 1972.
During the purge, Nagata, acting as vice-chairman of the URA, directed the killing of 12 members of the group by beatings or by forced exposure to frigid winter air temperatures.
A URA non-member who was present during the purge was also killed.
Arrested on 16 February 1972, Nagata was tried and convicted for her participation in the killings, and was sentenced to death.
While awaiting execution, Nagata died from brain cancer on 5 February 2011 at the Tokyo Detention House.