Holger Chen or Chen Chih-han (traditional Chinese: 陳之漢; simplified Chinese: 陈之汉; pinyin: Chén Zhīhàn; born March 12, 1979), is a Taiwanese internet celebrity, entrepreneur, political activist and mixed martial artist.

[2][3] He is also known popularly as Kuan Chang (Chinese: 館長; pinyin: Guǎnzhǎng; literally "gym manager") in Taiwan,[4] being the founder and CEO of G.K.

[9] After discharge from Marine Corps service, Chen was working odd jobs such as porter, deliveryman and salesman.

Being an internet celebrity and blogger, he often expresses his opinion on current affairs and politics through live streaming and social media platforms.

On December 17 2023, it was revealed Chen has taken up Brazilian Jiujitsu when he competed in a tournament in Okinawa hosted by Asian Sports Jiu Jitsu Federation (ASJJF)[10] as a ultra heavyweight white belt & winning first place in the white belt gi competition[11] and bronze in no-gi.

[12] In December 15, 2025, he again competed in a Brazilian Jiujitsu tournament in Taipei again as a white belt showing that he has taken an active role in promoting the sport in Taiwan.

[13] In 2019, Chen and New Power Party legislator Huang Kuo-chang organized a protest [zh] in Taipei against pro-China media.

Despite the pain caused by the bullets, Chen managed to host a live stream on Facebook regarding the incident.