Ajisaka Nagazane served as a bushō during the Sengoku and Azuchi-Momoyama periods. Nagazane was a retainer of the Uesugi clan. He served as lord of Shinjō Castle in Etchū Province and the commander of Nanao Castle in Noto Province. Nagazane had the title of Governor of Bitchū.
Similar to Kawada Nagachika and Yoshie Sukekata, Nagazane originated from Ōmi Province to serve Uesugi Kenshin of Echigo Province. From 1572, Nagazane became the lord of Shinjō Castle in the Niikawa District of Etchū. He fought against the Ikkō-ikki and contributed to the pacification of Etchū by Kenshin. In the ninth month of 1577, in the Second Battle of Nanao Castle, after Kenshin toppled (for the second time) Nanao Castle in Noto, the base of the Noto-Hatakeyama clan, he ordered Nagazane to serve as the commander in charge of the castle.
In the ninth month of 1579, owing to attacks by the Yusa and Nukui clans who had allied with Oda Nobunaga, Nagazane was expelled from Nanao Castle. His whereabouts thereafter are unknown. One theory is that he was demoted and returned to his home province of Ōmi.