He was the son of President Kaysone Phomvihane and Mrs. Thongvin Phomvihane, and came from a family of revolutionary cadres. He was one of five brothers. He was married to Dr. Viphavan Phomvihane, and they had two children, one son and one daughter.

At the age of six, he left his family to pursue his primary and secondary education in the Socialist Republic of Vietnam and the People's Republic of China. He subsequently pursued higher education and a career in Party and State affairs, serving in a number of important positions at provincial and central levels.

Education and Early Career

1962–1970: Studied at Bac Giang School in Vietnam and Nanning School in Guangxi Province, China.

1970–1973: Attended a higher education preparatory school in Ha Bac, Vietnam.

1974–1976: Studied at the Military School in Viengxay District, Houaphanh Province.

1977–1983: Studied at Moscow State University in the Soviet Union, now the Russian Federation.

1983–1984: Served as a lecturer at the National Institute of Politics and Public Administration in Vientiane Capital.

1984–1987: Conducted research and successfully defended his doctoral dissertation in Political Economy at the Academy of Social Sciences of the Soviet Union in Moscow.

Career in Party and State Affairs

1987–1989: Worked at the Savannakhet Provincial Office.

1989–1991: Served as Deputy Governor of Savannakhet Province and Head of the Department of Trade and Foreign Economic Relations.

1991–1993: Member of the Party Central Committee (5th term); Deputy Secretary of the Provincial Party Committee; Deputy Governor of Savannakhet Province; and Head of the Provincial Office.

1993–1995: Secretary of the Savannakhet Provincial Party Committee and Governor of Savannakhet Province.

1995–1997: Member of the Party Central Committee (6th term) and Minister of Finance.

1998–2001: Member of the National Assembly (4th term); Minister and Head of the Office of the Prime Minister.

2001–2006: Member of the Party Central Committee (7th term); Member of the National Assembly (5th term); Chair of the National Assembly's Foreign Affairs Committee; and Vice President of the National Assembly.

2006–2010: Member of the Party Central Committee (8th term); Secretary of the Party Committee of the National Assembly; Member of the National Assembly (6th term); Member of the Standing Committee and Vice President of the National Assembly; and Chair of the Foreign Affairs Committee.

2011–2015: Member of the Party Central Committee (9th term); Secretary of the Party Committee; Member of the National Assembly (7th term); and Member of the Standing Committee and Vice President of the National Assembly.

January–April 2016: Member of the Party Central Committee (10th term) and Politburo; Secretary of the Party Committee; Member of the National Assembly (8th term); and Member of the Standing Committee and Vice President of the National Assembly.

June 2016–2020: Member of the Party Central Committee (10th term) and Politburo; Secretary of the Party Committee; President of the Central Committee of the Lao Front for National Development; and Member of the National Assembly (8th term).

January 2021: Member of the Party Central Committee (11th term) and Politburo; Member of the National Assembly (8th term); and President of the Central Committee of the Lao Front for National Development.

March 2021–December 2025: Member of the Party Central Committee (11th term) and Politburo; President of the National Assembly (9th term).

January 2026: Member of the Party Central Committee (12th term) and Politburo.

March 2026: At the inaugural session of the 10th National Assembly, he was elected President of the National Assembly for the 10th term.

Throughout his career, Comrade Xaysomphone Phomvihane held a series of senior Party and State positions, contributing to national governance, legislative affairs, foreign relations, economic management, and the country's socio-economic development.

His long career in public service reflected his sustained contribution to the Party and State and to the national development of the Lao PDR.

KPL