In the early days, Sinshih District used to be the location of Singangshe, the biggest of the four Siraya settlements of the Pingpu People. Singangshe was also Taiwan's first community to make contact with western civilisation during the Dutch colonial era. The Dutch built mission schools and used the Roman alphabet to record the Siraya language, leaving behind the important Sinckan Manuscripts. When Prince Jheng Cheng-gong of Ming arrived, Sinshih became a key crossing for people traveling between the mountainous wilderness and Tainan City. To cater to travelers who had to stop and rest, the area eventually grew into a nascent town, leading to the name Sinshihzai (new town).
Singang Jhuang was established in the Sinshih area during Cing governance. On 15 May, 1901 during the Japanese occupation, the Sinshih Jie train station was established (this would become the TRA Sinshih Train Station today), leading to extremely rapid development. During Taiwanese administrative reforms of 1920, Sinshih Zhuang was established and placed under Sinhua Jun of Tainan Jhou (Tainan Prefecture). After the end of the Second World War, the region was renamed as Sinshih Town of Tainan County. In 1995, Southern Taiwan Science Park was established in the areas where Sinshih, Shanhua, and Anding districts meet. Many high tech companies began to establish factories in the area, bringing significant changes to the structure of ruralurban develop- ment. On 25 December, 2010, Tainan County and Tainan City were merged to become a municipality. Siang, Jhen, and Shih (town and cities) were renamed to Cyu (districts), while Cun were renamed as Li (Villages). Sinshih Township was therefore renamed as Sinshih District.