From Once Again to Bloodhounds, Lee Sang Yi has made his mark in the South Korean showbiz industry. The actor has showcased his diversity in acting, be it in the romance or suspense genre.

South Korean actor Lee Sang Yi is a versatile actor and also a singer who transitioned from a foundation in musical theatre to mainstream fame with shows including Hometown Cha-Cha-Cha and Once Again, among others. He is known for his charm and range, and he is also a member of the project vocal group MSG Wannabe.

Once Again tells the story of an elderly couple who are happily married with four children. However, the lives of their children go through various ups and downs that affect the parents. In the show he plays the role of Yoon Jae-seok—Gyu-jin's younger brother, Da-hee's love interest, and later her husband.

The romantic-comedy show tells the story of a dentist who moves to a seaside village where she meets a handyman intent on helping his neighbours. How the duo meet and love blossoms between them forms the main crux of the story. Lee Sang Yi plays the role of Ji Seong-hyun, a star variety show production director who is a workaholic and has a bright personality.

My Demon is all about Heiress Do Do Hee, who is an adversary to many, and Jung Koo Won is a powerful entity. When Jung Koo Won loses his powers, he must collaborate with Do Do Hee to regain them, and sparks fly between them as they embark on their journey. In this show, Lee Sang Yi plays the role of Joo Seok-hoon, Cheon-sook's nephew and CEO of Mirae Investment, an affiliate of Mirae Group.

It tells the story of a relationship that develops between the CEO and a dietitian at the same company. Lee Sang Yi is seen in Kang Ha-joon, CEO of GB Electric.

In No Gain No Love, it tells the story of how money-minded marketing professional Son Hae-yeong arranges a fake wedding with convenience store employee Kim Ji-uk to avoid missing out on a promotion. Somewhere down the line, real feelings develop between them. Lee Sang Yi is one of the main characters as Bok Gyu-hyeon.

Good Boy is about a group of Olympic medalists who join the police force through a special recruitment program, trading medals for badges as they tackle violent crimes and injustices with their athletic skills. Lee Sang Yi plays the role of Kim Jong-hyeon, formerly a silver medalist fencer. Jong-hyeon worked hard to graduate from the police academy due to his desire to reunite with his former girlfriend, Han-na.

The action-thriller show follows the story of two young boxers, who band together with a benevolent moneylender to take down a ruthless loan shark who preys on the financially desperate. The first season was released in 2023. Lee Sang Yi plays the role of Hong Woo-jin, Gun-woo's partner in action and a former Marine.