After working under Yukitaka and then his nephew Nobutsuna SANADA who succeeded Yukitaka, he also worked for his other nephew Masayuki SANADA, who took over the Sanada family after Nobutsuna's death at the battle of Nagashino, capturing Iwabitsu-jo Castle in Kozuke Province and becoming its Keeper.
幸隆や後を継いだ甥の真田信綱に従い、更に長篠の戦いで信綱が亡くなると、真田家を継いだ甥の真田昌幸に従って上野国岩櫃城を攻略し城代となった。