Sean Sih-Cheng Du is the Secretary-General of the Taiwan Tongzhi (LGBTQ+) Hotline Association. He joined Hotline as a volunteer in 2002 and has been since actively involved in the work on LGBTI+ and PLWHIV's rights. He became Hotline's Director of Policy Advocacy in 2011 and the Secretary-General in 2021.

His work includes social education, workplace equality, gay men's sexual health, and international affairs. He was a crucial member of the Marriage Equality Coalition Taiwan and a board member of the Persons with HIV/AIDS Rights Advocacy Association of Taiwan.

He is currently the East Asian Representative of the ILGA Asia Executive Board, a board member of the Taiwan Equality Campaign, and a member of the Taipei City Committee of Gender Equality. He has a master’s degree in Sociology from National Taiwan University.