Ruan Xiaohuan (Chinese: 阮晓寰; pinyin: Ruǎn Xiǎohuán; born 10 June 1977) is a Chinese dissident, blogger, and information security specialist. In 2009, Ruan started an anonymous blog named ProgramThink (Chinese: 编程随想; pinyin: Biānchéng Suíxiǎng) on Blogger, covering various topics from network security, methods to bypass the internet blockade in mainland China, to his own political commentaries (including criticism of the Chinese Communist Party) and book recommendations.

Ruan was captured on 10 May 2021 by the Shanghai police for his aforementioned blog. On 10 February 2023, he was convicted of “inciting subversion of state power” by the Shanghai No 2 Intermediate People’s Court, and sentenced to seven years of imprisonment with two years of deprivation of political rights and a confiscation of property of 20,000 Chinese yuan. On 13 December 2024, his appeal was dismissed by the Shanghai High People’s Court.