Hoverlab, a South Korean news commentary site on YouTube, claimed that the actor and the late actress Kim Sae-ron had been in a six-year relationship since she was 15 years old.

Kim Sae Ron and Kim Soo Hyun have been in headlines for their alleged relationship when the actress Kim Sae Ron was a minor and the actor Kim Soo Hyun was 27 years old. These headlines started since the actress Kim Sae Ron was found dead at her residence on Kim Soo Hyun's birthday and the pictures of them circulating all over the internet.

After denying their relationship several times, South Korean star Kim Soo-hyun has finally admitted he dated late actress Kim Sae-ron but denied she was underaged at the time. His talent management agency Gold Medalist issued a statement today (March 14): "Kim Soo-hyun and Kim Sae-ron were in a relationship from the summer of 2019 to autumn of 2020.