Thang Hoa San (Vietnamese: Thang Hoa Sân, Chinese: 湯華燊;^[1] born 28 August 1954) is an Australian chemist of Chinese-Vietnamese background.

Thang was born in Saigon in 1954 to Chinese parents who migrated to Vietnam in the 1930s.^[1] He completed his Bachelor of Science at Saigon University in 1976, and worked as a chemist at SINCO, a sewing machine manufacturer. In 1979, Thang left Vietnam as a refugee from the Vietnam War, and spent five months in a refugee camp in Malaysia before arriving in Brisbane, Australia later in the year.^[1] He enrolled at Griffith University where he completed an Honours degree in chemistry and a PhD in organic chemistry.^[2]

In 1986, Thang joined the CSIRO, the Australian government's scientific agency. In 1987, he left to join ICI Australia, but returned to CSIRO in 1990.^[2] In September 2014, research by Thomson Reuters for their citation laureate prize named Thang as one of a trio of CSIRO scientists (together with Ezio Rizzardo and Graeme Moad) most likely to be contenders for the Nobel Prize in Chemistry for their work in co-developing the reversible addition−fragmentation chain-transfer polymerization (RAFT) process. The three had shared the ATSE Clunies-Ross Award earlier that year.^[3] However, in December that year, Thang revealed that he had been laid off by the organisation in September, but had continued to work there unpaid in an honorary position.^[4] He later worked as a professor for Beijing University of Chemical Technology, and in May 2015, joined Monash University as a professor of chemistry and was elected as a Fellow of the Australian Academy of Science.^[5]