Sri Sultan Hamengkubawono X (Hanacaraka: ꦯꦿꦶꦯꦸꦭ꧀ꦡꦟ꧀ꦲꦩꦼꦁꦑꦸꦨꦮꦟ꧇꧑꧐꧇, also spelled as Hamengkubawana X, often abbreviated as HB X; born Bendara Raden Mas Herjuno Darpito, 2 April 1946) is the Sultan of the historic Yogyakarta Sultanate in Indonesia and is currently also the Governor of the modern Yogyakarta Special Region (Daerah Istimewa Yogyakarta).
 Hamengkubawono X succeeded his father, Hamengkubuwono IX as the Sultan of Yogyakarta when Hamengkubuwono IX died on 3 October 1988. Hamengkubuwono X was formally installed as Sultan on 7 March 1989. However, the position of the Governor of the Yogyakarta Special Region did not go to Hamengkubuwono X. Vice Governor Sri Paku Alam VIII, prince of the subordinate enclave of Paku Alaman within Yogyakarta was instead controversially elevated to the position of governor. This was contrary to the agreement made at the independence of Indonesia in recognition of Hamengkubuwono IX's support and role in the Indonesian War of Independence. Under the agreement, the Sultan holds the position of governor in the Yogyakarta Special Region, and the Paku Alam holds the position of vice governor.
 On 30 August 2012, following a decade of talks between Yogyakarta and the central government, the national legislature of Indonesia formally enshrined in law the convention that the Sultan inherits the position of governor.
 Hamengkubuwono X was a graduate of Public Administration at the Faculty of Law of Gadjah Mada University in Yogyakarta. He was active as Chairman of Indonesian Chamber of Commerce and Industry of the Special Region of Yogyakarta, Chairman of the Sports Committee of the Special Region of Yogyakarta, chairman and managing director of PT Punokawan Construction, President of the PG Madukismo Commissioner, and in July 1996 was appointed Chairman of the Special Region of Yogyakarta Expert Counsel to the Governor.
 Hamengkubuwono X followed the tradition of his late father Sri Sultan Hamengkubuwono IX in the spirit of Indonesian nationalism over self-interest by participating in street protests in support of the May 1998 student demonstrations opposing Suharto's rule, and like his illustrious father, wanted to be a pioneer in the Yogyakarta Reformation Movement albeit in a non-violent manner. He was also one of the four key figures in the early reform period that sparked the Ciganjur Declaration urging the government to hold elections as soon as possible, because President BJ Habibie had neither constitutional nor legal rights to take over the presidency of Suharto who had just resigned.
 Hamengkubuwono X has stated his vision for his region and the Sultanate are the development of science and technology, development of agriculture, tourism and world-famous cultural industries and thus provide a fair and prosperous life to all his citizens. He was nominated by popular choice, to the Golkar Yogyakarta Assembly as a presidential candidate for the 2009 Indonesian presidential election campaign. Hamengkubuwono X, though widely respected across all parties and nationwide as neutral, honest and uncorrupted was ultimately unsuccessful in garnering support outside Central Java and was unsuccessful to attain a first-round voting position.
 Hamengkubuwono X has discontinued the polygamist tradition of Javanese monarchs having several wives and possibly multiple concubines, as per his late father's wishes to modernize the royal system. He is married to Queen Hemas. Together they have five daughters, Crown Princess Mangkubumi, Princess Condrokirono, Princess Maduretno, Princess Hayu, and Princess Bendoro. His decision to appoint his eldest daughter as heir presumptive, ended the previously agnatic primogeniture succession and has become subject to controversies.
 Hamengkubuwono X resides in the Keraton Yogyakarta complex and uses the Governor's mansion solely for political affairs.
 Father — Sri Sultan Hamengkubuwono IX
 Mother — Raden Ajeng Siti Kustina (Bandara Raden Ayu Widyaningrum/Kanjeng Raden Ayu Widyaningrum/Raden Ayu Adipati Anum)
 In Javanese Kraton (palaces) names of individuals change with respect to change in status:
 His style and title in full English                  : His Majesty The Sultan Hamengkubuwono the Tenth, Commander-in-chief in war, Servant of the Most Gracious, Cleric and Caliph that Safeguards the Religion
  Japan: Order of the Rising Sun, Gold and Silver Star (2022)
 Honorary Degree of Doctor of Laws, University of Tasmania, Australia (2015) 
 2 concurrently serves as Sultan of Yogyakarta