Byun Sung Tae, known simply as Sungtae, is a South Korean actor and singer. He graduated from Jinwang High School. In 2017, he participated in "MIXNINE" under ASTORY Entertainment but was eliminated in the preliminary audition and did not make the broadcast. That same year, he featured in the MV of Iris's song "Me Too".

In 2019, he entered "Produce X 101" now under Urban Works Entertainment but he was eliminated in the 1st round and placed 66th overall. He made his debut in 2020 with a role in the webdrama "Do You Have a Part-Time Job?". He got support roles in "I Can See your MBTI" and in "Hometown Cha-Cha-Cha" in 2021, with the latter role getting him noticed by the audience. He earned a lead role in the BL drama "Happy Merry Ending" in 2023. He is currently represented by DSP Media.