Lee Soo-man (Korean: 이수만, born 18 June 1952) is a South Korean business executive and record producer who is best known for being the founder of SM Entertainment, a multinational entertainment company based in Seoul. He has also been referred to as the "president of culture", as one of the pioneers of the Korean Wave. Lee debuted as a singer in 1971 while he was a student at Seoul National University. In 1989, he founded SM Entertainment, which has since become one of the largest entertainment companies in the country.

Lee was born in Jeonju, South Korea, on 18 June 1952, and attended Seoul National University on and off between 1971 and 1979. Lee debuted as a member of the band April and May (사월과 오월, alternatively 4월과 5월) in 1972 (he had joined the band in 1971), but he later departed from it for health reasons. He gained spotlight for his "good boy" image, supported by the fact that he was one of the few people who were not involved in the weed scandal among Korean celebrities in 1975, and his high academic credentials in Seoul National University. He became known for hit songs such as "행복 (Happiness)", released in 1978, and "한송이 꿈 (A Piece of Dream)" released in 1976. In 1977, he was a member of the Korean indie band Sand Pebbles [ko]. In addition to his career as a musician and his studies in university, he worked as a radio DJ and TV host during this time. Lee Soo-man was also known for his trio with singers Lee Moon-sae and Yoo Yeol [ko] called Masamtrio (馬三트리오), named as such because of their appearances that resemble that of a long face of a horse. In 1980, he formed the band 이수만과 365일 (Lee Soo-man and The 365 Days). However, media censorship policies under the Chun Doo-hwan government discouraged him from a career in the Korean music industry.^{[citation needed]}

In the early 1980s, Lee decided to leave the entertainment world in order to pursue a career in computer engineering. He went abroad to work on a master's degree at California State University, Northridge, where he witnessed the rise of "superstars of the MTV generation" such as Michael Jackson. Inspired by the heyday of MTV in the United States, Lee set his sights on laying the foundation for the modern Korean pop music industry. In 1985, he returned to Korea "with a vision of what the Korean music industry could be."

Following his return to Korea, Lee ventured back into the entertainment world by working as a DJ and presenter. In 1989, after four years of saving money and gaining experience in the industry, he established an entertainment company called SM Studio (named after his initials) in the Apgujeong neighborhood of Seoul, and signed singer Hyun Jin-young. During the 1990s, SM Studio developed an in-house system that looked after all aspects of its artists' careers. Lee's approach was targeted at teenage audiences, and took a holistic view of the qualities needed to become a successful entertainer. The company was renamed SM Entertainment in 1995. In 1997, he founded the music production company Like Planning.

In February 2010, Lee resigned from his position as a member of SM's board of directors, but maintained a role in the company's "management and artist development" divisions. He continued to exert influence over SM through his production company, Like Planning, taking 6% of their revenue as a consultancy fee for his involvement in the music production process. He remained the biggest shareholder, controlling the company's management rights. He founded the music publishing company Culture Technology Group Asia in May 2015 and drone company LeePollux in February 2019.

In 2019, KB Asset Management, SM's third-largest shareholder, sent an open letter to the company complaining that Like Planning was taking 46% of SM's operating profit each year. They demanded a merger between Like Planning and SM, which the company rejected. On 23 January 2020, Lee Soo-man was listed by Billboard as one of the world's influential music industry leaders. He worked on South Korean girl group Loona's 2020 EP [#], which was his first ever project away from his namesake SM Entertainment.

In October 2022, SM announced that they would terminate their production contract with Lee's Like Planning by the end of the year. On 3 February 2023, SM said that they would restructure the company without the help of Lee, adopting a multi-production center system to replace his role as chief producer. Kakao Entertainment purchased a 9.05% stake in SM, making them the second-largest shareholder, and signed a business agreement with SM to fund their plans. Lee, objecting to this, filed an injunction against the issuance of new shares and convertible bonds, which was upheld by the court. He sold his stake in SM to Hybe Corporation, making them the biggest shareholder. Hybe announced their intention to acquire the company with Lee's support. This sparked a battle for SM's management rights, pitting Lee and Hybe against the SM executives and Kakao.

Lee Sung-soo, SM's co-CEO and Lee's nephew by marriage, uploaded a video to YouTube in which he levelled a series of accusations at Lee. In the video, he claimed that Lee had founded a company called CT Planning Limited in Hong Kong in 2019 to evade taxes, through which he was taking 6% of earnings from artists' overseas activities. The company had been established using SM's assets but was owned solely by Lee, and was the foreign equivalent of Like Planning. He also said that Lee wanted to force artists to publicly declare his importance to the company and attempted to insert environmental references into songs to promote his business interests. The National Tax Service said they would investigate the claims of tax evasion. Lacking the funds of their competitor, Hybe eventually withdrew from the takeover battle, enabling Kakao to become the largest shareholder and obtain management rights. Lee released a statement saying he was "moving toward the future".