Mahitala Dhibesra Adulyadej Vikrom, the Prince Father ( , 1 January 1892 – 24 September 1929), formerly Mahidol Adulyadej, Prince of Songkla () or Mahidol Songkla, was the father of King Ananda Mahidol (Rama VIII) and King Bhumibol Adulyadej (Rama IX) of Thailand, and the paternal grandfather of King Vajiralongkorn (Rama X). He was also regarded as the father of modern medicine and public health in Thailand. He also founded the House of Mahidol or the present Royal Family of Thailand.