The name given to this period is based on the name of the castle where Nobunaga ODA resided, Azuchi-jo Castle, and the name of the castle where Hideyoshi TOYOTOMI resided, Momoyama-jo Castle (also known as Fushimi-jo Castle).
織田信長の居城であった安土城、豊臣秀吉の居城であった伏見城（桃山）から、このように呼ばれる。