Nguyễn Mạnh Tường (1909–1997) was a Vietnamese lawyer and intellectual. He was known to be one of the active participators in the Nhân Văn affair in the mid 1950s which saw many middle class intellectuals demanding for freedom and democracy in communist-led North Vietnam. After he criticised the disastrous land reform campaign in 1956, he was stripped of all positions he held in the government and was forced to retire from practicing law.
Returning to Vietnam in 1936, Nguyễn Mạnh Tường taught French literature in Hanoi at the Lycée du Protectorat (trường Trung học Bảo hộ or trường Bưởi, since 1945 named Chu Văn An High School). Dissatisfied with prejudiced French policies, he left the school and opened a law firm.
While participating in the Vietnamese resistance against France (see First Indochina War), he worked as a lawyer and taught in Thanh Hóa until the Partition of Vietnam in 1954, when he moved back to Hanoi and became a professor at University of Literature (Đại học Văn khoa, now Vietnam National University, Hanoi).
After 1954, he became dean at the Hanoi University of Law (Đại học Luật Hà Nội), vice-chairman of the Vietnamese Lawyers Association (Hội Luật gia Việt Nam); chair of the Vietnam Law Group (Đoàn Luật sư Việt Nam); vice-dean at the Hanoi National University of Education (Đại học Sư phạm Hà Nội); member of the Central Committee of the Vietnamese Fatherland Front; member of the Vietnam-France Friendship Society (Hội Hữu nghị Việt-Pháp), Vietnamese-Soviet Friendship Society (Hội Hữu nghị Việt-Xô), and Committee for the Protection of World Peace (Uỷ ban Bảo vệ Hoà bình Thế giới); founder of the Unity Club (Câu lạc bộ Đoàn Kết); and vice-provost at Hanoi National University of Education; he also conducted education research. He joined the Vietnamese government delegation at diplomatic talks in Đà Lạt and other peace talks in Beijing and Vienna.