Kyari was born on 23 September 1952, to a Kanuri family from Borno. He attended St. Paul's College in Wusasa Zaria,
Abba Kyari
He was married to the sister-in-law of Ibrahim Tahir, and had four children, Aisha, Nurudeen, Ibrahim, Zainab.
He graduated with a bachelor's degree in sociology from the University of Warwick in 1980, and also obtained a law degree from the University of Cambridge was called to the Nigerian Bar in 1983 after attending the Nigerian Law School.
In 1984, he obtained a master's degree in law from the University of Cambridge. He later attended the International Institute for Management Development in Lausanne, Switzerland, and in 1992 and 1994 participated in the Harvard Business School's Program for Leadership Development.
Upon his return to Nigeria he worked for the law firm Fani-Kayode and Sowemimo for some time.
From 1988 to 1990, he was Editor with the New Africa Holdings Limited Kaduna. He also served as a Commissioner for Forestry and Animal Resources in Borno State in the 1990s.
He was the secretary to the board of the African International Bank Limited, a subsidiary of Bank of Credit and Commerce International From 1990 to 1995.
He was an executive director in charge of management services at the United Bank for Africa, and was later appointed the chief executive officer. In 2002, he was appointed a board director of Unilever Nigeria, and later served on the board of Exxon Mobil Nigeria.
He was appointed Chief of Staff to President Muhammadu Buhari in August 2015, he quickly became an influential figure within the Buhari administration. During the administration's first term, he worked mainly behind the scenes to implement the president's agenda.
In 2019 with Buhari's re-election for a second term, Buhari ordered his cabinet to channel all requests through Kyari's office. Further enhancing his influence within government circles, and being labelled as the de facto head of government. He was undoubtedly the most powerful Chief of Staff Nigeria ever had.
In 2017, following a leaked memo, Kyari became embroiled in a public argument with the Head of Civil Service, who was later removed from office and arrested.
In 2020, in another leaked memo, Babagana Monguno the National Security Adviser accused Kyari of meddling in matters of national security.
On 24 March 2020, it was made public that Kyari tested positive for COVID-19 on 23 March, following an official trip to Germany nine days before. There were reports that he had been flown out of the country for treatment, and Reuters later reported he had "a history of medical complications, including diabetes".[
On 29 March 2020, in an official statement, Kyari announced he was being moved from isolation in Abuja to Lagos for "preventive treatment".
He died on the evening of 17 April 2020 at age 67. He was eulogized by The Economist as “a largely honourable man who went to the heart of a thoroughly corrupt and dysfunctional system, aiming to reform it—but who struggled to overcome its inertia amid a series of crises.”
