He is the youngest son of Lee Sung-im and Oh Yoo-geun, the former Deputy Speaker of the Seoul Metropolitan Council.

[2] He joined Yeonwoo Stage in 1991, then subsequently appeared to Ride Together (동승),[2] which was adapted from a drama of Ham Se-dŏk.

[6] After his admission to K-ARTS in 1994, he continued his acting in Marionette Show (꼭두각시 놀음), The Story of Park Ki-hong (박기홍 이야기), Mud (진흙) and so on.

[9] Following the defeat, he worked for Park Geun-hye, the Saenuri's presidential candidate who won in the same year, as well as the party's youth wing.

[3] The election of Lee Sang-kyu was annulled due to the UPP's ban in December 2014,[10] which brought a by-election in 2015.

[19] Soon, the party was split due to the conflicts regarding the electoral reform and the installation of the Office of Crime Investigation for Senior Public Officials.

[20] This occurred the resignation of Kim Kwan-young, the party's parliamentary leader who faced public criticisms.

[27] During the 2015 by-election, it was reported that Oh's master's degree from Korea University was revoked due to the thesis plagiarism, which he forgot to write the references.