Comparing Kim Soo Hyun’s Handwriting To His Alleged Handwritten Letters To Kim Sae Ron

This article is part of our coverage of Kim Soo Hyun And Kim Sae Ron's Relationship. You can read more and view the entire timeline here.
In an exposé released by former media reporter Kim Se Ui on the controversial YouTube channel Garo Sero Research Institute, the aunt of Kim Sae Ron alleged that Kim Soo Hyun began dating Kim Sae Ron when she was 15 and he was 27. Since the exposé, photographic and written evidence to support this claim has been released.

The written proof revealed by Garosero Research Institute includes a postcard Kim Soo Hyun allegedly sent Kim Sae Ron from Paris and a long, detailed letter that he allegedly wrote when he was a 30-year-old soldier and Kim Sae Ron was 17.

When the dating rumors arose in 2024, after Kim Sae Ron posted an intimate photo of her and Kim Soo Hyun on her Instagram, Kim Soo Hyun’s agency, GOLD MEDALIST, stated that the rumors were “unfounded.”

We would like to inform you that the rumors of Kim Soo Hyun being in a relationship [with Kim Sae Ron] are unfounded. The photo that is being spread online appears to have been taken in the past when the two were both under our management. As for Kim Sae Ron’s intentions for uploading the picture, we do not know.
— GOLD MEDALIST
Most recently, in regards to Garo Sero Research Institute‘s exposé, the agency stated:
Hello, this is Gold Medalist.
We would like to comment on the recent broadcast from Garo Sero Institute about Kim Soo Hyun.
We will be releasing a full statement next week to set the record straight, correct false statements, and counter the baseless rumors that were presented about Kim Soo Hyun.
We apologize for causing exhaustion with the length wait. Please understand as this is to avoid continuous statement releases.
Thank you.
— Gold Medalist
Proving the relationship allegations false could involve discrediting and disproving Garo Sero‘s evidence, including the handwritten letters supposedly written by Kim Soo Hyun. Part of this process could potentially involve proving that A) Kim Soo Hyun did (or didn’t) write the letters, and B) the recipient was (or wasn’t) Kim Sae Ron.
Kim Sae Ron is not addressed by name in the letter or the postcard, but she is referred to as “Saero-Nero,” a nickname. Kim Sae Ron personally used that nickname for the caption of an X (formerly Twitter) post that she tweeted when she was 15 years old.
새로네로 pic.twitter.com/sXq8Kqgee1
— 김새론 (@yuk0731) May 20, 2016
Now, let’s take a closer look at the handwriting. This message was written by Kim Soo Hyun in 2013, two years before he allegedly began his six-year relationship with Kim Sae Ron.
Kim Soo Hyun's handwriting looks like my handwriting too ! #kimsoohyun pic.twitter.com/BLpuMiNEWj
— 김수현 (@kimsoohyunlove) August 27, 2013
Kim Soo Hyun also filled out this profile around the same time.
KimSooHyun's handwriting and drawing pic.twitter.com/aFS9Jy6I #HappyBirthdayKimSooHyun
— Kim Soo Hyun 김수현 (@KimSooHyun_Love) February 15, 2013
For comparison’s sake, here is a side-by-side image of the 2013 message (left) and a portion of Kim Soo Hyun’s postcard dated 2019 (right).
There is also this message, written by Kim Soo Hyun after he became the new face of COSRX, a cosmetics brand, in 2020.

Hello.
I am Kim Soo Hyun, a model for COSRX.
Please look forward to a brighter tomorrow with COSRX!— Kim Soo Hyun’s writing
Here is a side-by-side of Kim Soo Hyun’s 2018 letter from the military (left) and the COSRX message (right), both written in marker. Does the handwriting match?
Read all of the alleged written evidence here:
All The Written Proof Of Kim Soo Hyun And Kim Sae Ron’s Alleged Relationship So Far