Lawyer Kang Yong Suk of YouTube channel 'Garo Sero Institute' has made claims that Kim Gun Mo's wife Jang Ji Yeon had a complicated dating life that involved actor Lee Byung Hun. 

Kang Yong Suk held a talk where he stated that Jang Ji Yeon had previously dated Lee Byung Hyun. Kim Gun Mo's representatives have made a quick response on January 21st, stating that "the news has nothing to do with the marriage, and we cannot tolerate attacks on the family for claims regarding men that cannot be proved. We will take strong legal action against malicious and attacking comments."

The scandal involving Garo Sero Institute and Kim Gun Mo has been going on since last September since multiple alleged victims have claimed that they have experienced sexual assault at the hands of the veteran singer. Meanwhile, Jang Ji Yeon and Kim Gun Mo have filed their marriage certificate last October.