[4][5] He rose to fame in the historical coming-of-age drama Sungkyunkwan Scandal (2010) and the variety show Running Man (2010–2011) as one of the original cast members.

Since then, he has played a diverse roles in the television series – The Innocent Man (2012), Descendants of the Sun (2016), Arthdal Chronicles (2019), Vincenzo (2021), and Reborn Rich (2022); as well as the films A Werewolf Boy (2012), The Battleship Island (2017), and Space Sweepers (2021).

He excelled in his studies all through high school and scored 380 points out of 400 on his national college entrance test,[13] gaining admission to Sungkyunkwan University.

[14] While in Seoul preparing for the entrance test, he was scouted on the subway by an agent but did not immediately enter the entertainment industry as he was still ambivalent about his career path,[15] and because his father had initially been against him becoming an actor.

[16] He continued to study part-time after deciding to enter the entertainment industry full-time during his third year of university,[17] eventually graduating with a degree in Business Administration (minor in broadcasting) in 2012.

[21] The following year, he appeared in the couple-swapping segment "Believe in the Moment" of omnibus Five Senses of Eros and continued to take on small but notable roles in Triple and Will It Snow for Christmas?.

[37] Critics praised Song's performance, calling it a portrayal of a genius who "realizes the futility of power early in life" and hides in his books to cope with growing up under the rule of his tyrannical father Taejong.

[50] In preparation for his role, Song watched nature documentaries and observed stray dogs on the streets to learn how to mime and imitate the body movements of an animal.

[51][52] He also repeatedly watched Tim Burton's 1990 romantic fantasy Edward Scissorhands, Matt Reeves' 2010 vampire flick Let Me In, and Gollum in The Lord of the Rings.

[58] The drama attracted high ratings, which along with the impressive box office run of A Werewolf Boy, cemented Song's image in the press as the "savior" of the melodrama genre both on the big and small screen.

[94][95][96] In January 2020, Song left Blossom Entertainment and signed with History D&C, a newly launched talent management and content production company founded by former SidusHQ executive Hwang Ki-yong.

[97][98] In 2021, Song starred in the science fiction film Space Sweepers alongside Kim Tae-ri, directed by Jo Sung-hee, released exclusively on Netflix on February 5, 2021.

[102] Song was then cast in the fantasy revenge series Reborn Rich directed by Jeong Dae-Yoon, adapted from the popular web novel of the same name.

[107] He is set to appear in the criminal thriller film Bogota: City of the Lost alongside Lee Hee-joon and Kwon Hae-hyo, which will be directed by Kim Seong-je.

"[112] In 2011, after effectively playing the younger version of King Sejong in Deep Rooted Tree that made him trend in web portals, he earned the title "good actor Song Joong-ki.

[114][115] In 2016, after portraying Army Captain Yoo Shi-jin in Descendants of the Sun, he was made the Korea Tourism Organization's Honorary Ambassador, topped popularity polls in Asia, and became a CF King.

[116][117] In China, the public safety Weibo page and the Chinese government has had to issue statements cautioning against overindulgence of the actor and the drama, citing cases of plastic surgery, domestic violence and divorce as a direct result.

[136] After years of aversion to social media, Song opened his official Instagram account under the username "hi_songjoongki" on February 14, 2021, directly managed by his agency History D&C.

Song said the fans were like his wings for they lift him up, emotionally and financially, by voting for him and buying the products he endorses as well as watch all his movies and TV shows.

[141] In 2011, Song was chosen as the ambassador for the Good-hearted Library Project, a talent donation campaign by the Standard Chartered that allows the public to participate in the production of audiobooks for the visually impaired.

[142][143][144] In 2013, Song and Ha Ji-won were appointed as honorary ambassadors of medical tourism by South Korea's Ministry of Health and Welfare.

[151] This has inspired his official fan club Ki Aile to celebrate his birthdays by donating transplant fees to help patients with leukemia and cancer.

[158][159] In 2015, during his military service, he donated 100 million won to the UNICEF Korea Committee to help the children and victims of the April 2015 Nepal earthquake.

[178] In the digital and technology sector, Song was chosen for the brand Xbox 360 Kinect because of his "childlike, innocent, and healthy" image that matches the new hands-free game controller and LG XNote with Shin Min-a in 2011.

[184] Soon after starring in drama The Innocent Man and film A Werewolf Boy in 2012, Blossom Entertainment reported that Song was on his way to become the next CF King with 10 endorsement deals under his belt.

[189] The Korea Broadcast Advertising Promotion Corporation (KOBACO) "2016 Consumer Behavior Survey" picked Song as the best model to represent South Korean brands.

[190] Some of his ad include Baskin Robbins,[191] LG Household & Health Care,[192] KT,[193] Forencos,[194] Jeju Air,[195] Hite Jinro,[196] Cuchen,[197] as well as lucrative Chinese products like Proya with Zhang Ziyi,[198] Tencent,[199] and VIVO.

He was paired with Thai actress Mew Nittha on TV, digital, and outdoor ads on the busiest Bangkok Mass Transit System stations in Chit Lom, Siam and Phrom Pong.

[206][207][208] They married in a private ceremony on October 31, 2017, at Youngbingwan, Hotel Shilla in Seoul, amid intense media interest across Asia with his closest family and friends.

[215] On January 30, 2023, Song announced through his fancafe that he had married his British girlfriend Katy Louise Saunders, a former actress who was already pregnant with their first child.