In later years he seems to have gone to the capital, Kyoto, and in 1335 he participated with his father Yoshisuke in the army of his uncle Yoshisada NITTA, who had been ordered to search for and kill Takauji ASHIKAGA, a rebel against the Kenmu government.
その後、上京したと見られ、建武(日本)2年（1335年）、伯父新田義貞が建武政権に反旗を翻した足利尊氏への追討令を下されると、父・義助と共にその軍に加わる。