Thanks to his elder brother Nagatoki HOJO's appointment as a hyojoshu (a member of Council of State) in July 1256, he was appointed to Kitakata (Northern Chief) of Rokuhara Tandai (an administrative and judicial agency in Rokuhara, Kyoto), and went up to Kyoto, substituting his brother (Nagatoki), and since then, he took care of the post of Tandai (administrative and judicial agency) during 14 years until he died young on February 25, 1270 at the age of 31.
建長8年（1256年）6月からは兄北条長時が評定衆に任じられたため、兄に代わり六波羅探題北方に任じられて上洛し、文永7年（1270年）1月27日に31歳の若さで死去するまで14年間に渡って探題職を務めた。