Taiwan has been an important stronghold in the Pacific Ocean since the Age of Discovery. Tainanfu, Lugang, and Bangkah were three critical commercial port cities that played a crucial role in the trading history of Taiwan. These three cities witnessed Taiwan’s involvement in the international trade zone and symbolized its busy business activities starting in the seventeenth century. This article investigates records created by a Qing official Shen Bao-zhen, the Hsu family enterprise in Lugang, and the Chen family enterprise in Nagasaki to illustrate the rich history of these three port cities.