John Ambrose, commonly known as John Ambrose Dumpangol (born 3 March 1952) is a Malaysian politician who served as a Senator from January 2018 to January 2024. He is a Supreme Council Member of the Parti Gagasan Rakyat Sabah (GAGASAN), a component party of the Gabungan Rakyat Sabah (GRS) coalition. He is formerly a member of Malaysian United Indigenous Party of Sabah (Sabah BERSATU), a former component party branch of the GRS coalition and component party of the Perikatan Nasional (PN) coalition and formerly a member of the United Malays National Organisation of Sabah (Sabah UMNO), a branch of a component party of the Barisan Nasional (BN) coalition.
He is of Kadazan-Dusun descent and is a Christian of the Roman Catholic denomination.
He served as the UMNO Division Chief of Penampang since 2004 prior to leaving the party on 13 December 2018 to joined BERSATU on 15 March 2019 and moved to Sabah BERSATU after its formation on 6 April 2019. He then left Sabah BERSATU on 10 December 2022 and joined GAGASAN on 5 February 2023.