| Ignatius Datong Longjan | |
| Office1: | Senator for Plateau South |
| Term Start1: | 11 June 2019 |
| Term End1: | 10 February 2020 |
| Predecessor1: | Jeremiah Useni |
| Successor1: | Nora Daduut |
| Office2: | Deputy Governor of Plateau State |
| Governor2: | Jonah David Jang |
| Term Start2: | 29 May 2011 |
| Term End2: | 29 May 2015 |
| Predecessor2: | Pauline Tallen |
| Successor2: | Sonni Gwanle Tyoden |
| Office3: | Chief of Staff to the Governor of Plateau State |
| Governor3: | Jonah David Jang |
| Term Start3: | 29 May 2007 |
| Term End3: | 29 May 2011 |
| Successor3: | Gyang Pwajok |
| Birth Date: | 19 May 1944 |
| Death Place: | Abuja, Nigeria |
| Nationality: | Nigerian |
| Party: | All Progressives Congress |
Ignatius Datong Longjan (19 May 1944 – 10 February 2020) was a Nigerian diplomat and politician who served as the senator representing the Plateau South senatorial district from 2019 until his death in 2020.[1] He previously served as the deputy governor of Plateau State from 2011 to 2015.[2]
Longjan was born in Kwa, Quanpaan Local government area of the present day Plateau State. He attended the Kwa Junior/Senior Primary School and St. Joseph's College, Vom. He then attended the Ahmadu Bello University Zaria for his university education, where he obtained a Diploma in Law, and also attended the City University of New York, where he obtained a bachelor's degree in public administration.
Most of his working life was spent in the Nigerian foreign service in Nigerian missions abroad including Hamburg in Germany, The Hague in Holland, Conakry in Guinea, New York in the USA and Moscow in Russia.
Longjan was the chief of staff to the Plateau State governor between 2007 and 2011. He subsequently became the deputy governor of the state between 2011 and 2015. In 2019, he contested the election to represent the Plateau Southern senatorial seat in the Nigerian National Assembly. At his party's primary selection, he scored 972 votes to beat the other contestants for the party's ticket.[3] In the 25 February 2019 general election, he polled 140,918 votes to win the election.[4]
On 10 February 2020, Longjan died at a hospital in Abuja, Nigeria.[5]