Mangkunegara IX (born 1951) is the current traditional ruler of the former state of Mangkunegaran, located in Java, Indonesia.
He succeeded his father, Mangkunegara VIII, as Prince of Mangkunegaran on 3 September 1987.
His full royal name is Kanjeng Gusti Pangeran Adipati Arya Mangku Negara.
Prior to his accession he was named Gusti Pangeran Hadiningrat Sujiwakusuma.
In the meantime Sujiwakusuma became viceroy in Mangkunegaran.
His accession was controversial because for the first time in Indonesian history, Mangkunegaran involved relatives outside the core to participate in the decision.