Diệu was born in 1828 into a family of officials in Điện Bàn District, Quảng Nam Province. In 1848, he passed the Thi Hương/Xiangshi or Township Test. In 1853, he became a phó bảng/Fubang and thereafter, a cử nhân/Juren. In 1864, he suppressed Nguyễn Phúc Hồng Tập's rebellion. He was then posted to Bắc Giang Province, Nam Định Province and Bắc Ninh Province respectively. In 1879, Hoàng Diệu was appointed as the governor of Hanoi. He committed suicide by hanging when the French under captain Henri Rivière, having exceeded his superiors' orders, suddenly took the citadel of Hanoi on 25 April 1882.
Hoàng Diệu is venerated alongside Nguyễn Tri Phương by the Vietnamese people as loyal subjects who sacrificed themselves for Vietnam. Many cities and streets in Vietnam are named after him.
His grandson was the Paris-trained philosopher Phan Khôi.
- Bradley Camp Davis, States of banditry: The Nguyen government, bandit rule, and the ... - Page 232 University of Washington - 2008 "Consistent with his threat and to the great shock of Hoang Dieu, Riviere occupied the citadel on April 26. The entire attack lasted less than an hour, and ended with only four French soldiers wounded.15 Hoang Dieu, defeated and ashamed, ."
- Đình Hoà Nguyêñ From the city inside the Red River: a cultural memoir of Hanoi Page 76 - 1999 "The governor was said to have sent an apologetic message to the emperor (based in Hue) to confess his failure in defending the citadel with an outnumbered and out-equipped army. At any rate, Hoàng Diệu dismounted from his elephant,"
- Knowledge on Viet Nam through ancient post cards Khắc Cần Nguyễn, Cao Lê Nguyễn, Thị Thu Hằng Đoàn - 2002 "In 1883, Hanoi Provincial Governor Hoàng Diệu committed suicide_and was buried near the Education Hall (now the new Hanoi Railway Station) in Trấn Quý Cáp Street.
- Dictionary of Battles and Sieges: F-O - Page 433 Tony Jaques - 2007 "Carrying 250 reinforcements, his ships then bombarded the citadel and took it by storm after Governor Hoang Dieu hanged himself to avoid capture."