Dasi was an important trading port of Dahan River in the 19th century. When the North-South Railway, which bypasses Tasi, was completed in 1909, the importance of river trade decreased. Dasi is no longer a trading port. On the other hand, the production of wooden furnitures became famous.
DasiTownship is located at slightly eastward from the middle of Taoyuan, adjacent to Pingjhen City in the west, Longtan Township in the southwest, Bade City in the northwest, Fusing Township in the southeast and Yingge Township and Sansia Township in the northeast.
The measure of entire Dasi is 105 square kilometers and occupies 9% of Taoyuan County, which is the second administrative district of Taoyuan County and only behind Fusing Township in the territory.
Dasi Prefecture Office which the system was in use till the period of the Nationalist Government’s rulership was then set up at the original location of Nanya Hall (This is where the present DasiTownship Office is).