Siauw Giok Tjhan (Chinese: 蕭玉燦; pinyin: Xiāo Yùcàn; 23 March 1914 – 20 November 1981) was a Chinese Indonesian activist and politician.

Born in Kapasan, Surabaya, East Java, Indonesia, he was an independent member of the Provisional House of Representatives in the early 1950s.

He was briefly detained without charge during the August 1951 mass arrests.

He was active in rights campaigning and was part of Baperki as the group's leader.

He supported the Communist takeover of China, opposed to Taiwan, and was a Marxist.