| Hangul: | 대도수 |
| Rr: | Dae Do-su |
| Mr: | Tae To-su |
Tae To-su was a Goryeo military official who served in the Goryeo-Khitan Wars. He was a scion of the royal family of Balhae, some who had fled to Goryeo after its fall to the Khitans.
It is thought that Tae To-su was either the son or grandson of Tae Kwang-hyŏn, the crown prince of Balhae who fled to Goryeo. The genealogies of the Hyŏpgye T'ae clan, the Yongsun T'ae clan, and the Miryang Tae clan all claim that he was the son of Tae Kwanghyon. He had a son named Tae Hyŏng-in, and a grandson named Tae Hong-yun .[1]
During the First Goryeo-Khitan War, Tae served as a senior colonel, defending at the Battle of Anyung-jin . Alongside junior colonel, the Goryeo army was able to emerge victorious at Anyung-jin, defeating Liao general .[2] By the time of the Second Goryeo-Khitan War, Tae became a general. In 1010, he was defending Seogyeong from the Liao. Tae planned an attack on the nearby Liao troops with fellow Goryeo commander T'ak Sachŏng. However, when the time came, T'ak did not send his troops, causing Tae's loss and capture by the Khitans.