Civil official from Jungjong to Seonjo who served as Minister of War, Left Consultant and Panjungchubusa; pen name Samyangjae, posthumous title Chungjeong (a different person from the Hadong Jeong namesake)
Same-name figures:
정응두(鄭應斗) — Independence Patriot · Domestic Anti-Japanese Resistance · Domestic Anti-Japanese Resistance

| Life | 1508 ~ 1572 |
| Era | 조선 전기 |
| Clan | 나주 정씨 |
Jeong Eung-du (丁應斗, 1508-1572) was an early Joseon civil official from Naju, with courtesy name Chugyeong, pen name Samyangjae and posthumous title Chungjeong. He was the son of Jeong Ok-hyeong and grandson of Jeong Su-gang, a 14th-generation member of the Naju Jeong. He is a different person from the Hadong Jeong independence activist (born 1917) of the same name.
The central clan association says he passed the licentiate examination at 24 (1531) and the civil examination at 27 (1534); Wikipedia and the heritage explanation of the stele say he placed first in 1534. Sources differ on the licentiate year (1531 per the association, 1521 per the heritage text) and on his rank at the civil examination ('first' versus 'second'). He started as a Director at the Office of Construction and went through Senior Counsellor of Personnel and Left Royal Secretary to become Minister of War, Governor of Pyeong-an and Left Consultant, rising to Panjungchubusa in 1566 (21st year of Myeongjong).
The association says he governed several of the eight provinces and went to Ming China twice as envoy of thanks. Despite his rank he disliked silk clothing and lived frugally, visited his grandmother, past eighty, whenever he could between duties, and during his mother's mourning built a hut by her grave and walked there daily. It also tells that he gave his early-widowed elder sister first share of any money he received.
All four of his sons became prominent: Jeong Yun-jo as a Palace Secretary, Jeong Yun-hui as a first-place examinee and Governor of Gangwon, Jeong Yun-u as a Hongmungwan official and Governor of Gangwon, and Jeong Yun-bok as Inspector-General. His wife is said to be a daughter of Magistrate Song Chung-se. He died in 1572.
Wikipedia gives first place for his 1534 civil examination, while the clan association's notable-persons page says second place; its Nine-Generation Okdang page also says first place, so even association materials differ. The licentiate year is likewise given as 1531 or 1521.
The association's materials say that although he governed provinces and rose to minister, he avoided silk clothing. These anecdotes come from clan records and were not cross-checked against the Veritable Records.
The association's literary roll and exam-passers list give Jeong Yun-jo (1528-1586) as Palace Secretary of the Royal Clan Office, Jeong Yun-hui (1531-1589) as Governor of Gangwon, Jeong Yun-u (1539-1605) as Governor of Gangwon, and Jeong Yun-bok (1544-1592) as Inspector-General. Three of them are said to have served in the Hongmungwan.
The stele of Jeong Eung-du was erected in 1728 and, together with his father's, is Gyeonggi Provincial Cultural Heritage Material No. 91, at the entrance of the clan graveyard at Jeil-ri, Yangji-myeon, Yongin.
He was first buried at Haengju Neunggok in Todang-ri, Goyang, and moved in October 1988 to the Jeil-ri clan graveyard in Yongin, per the central clan association. His spirit-way stele was erected in 1728.
His four sons were Jeong Yun-jo, Jeong Yun-hui, Jeong Yun-u and Jeong Yun-bok; grandsons such as Jeong Ho-gwan and Jeong Ho-seon passed the civil examination.