Arima Haruzumi (有馬 晴純, 1483 – March 19, 1566) was a Japanese feudal lord in the Sengoku era. Initially known as Arima Sadazumi, he held the title of Shuri-dayu and a position in the shobanshu, the private guard of the Shogun. His tenure as lord had the Arima at the height of their power, controlling trade in the strategically important Shimabara Peninsula, near modern-day Nagasaki. Ashikaga Yoshiharu, the 12th Ashikaga shogun, recognizing his strategic importance and strength, allowed him to take a character from his name and call himself "Haruzumi."