Shuangyu was a port located on Liuheng Island off the coast of Zhejiang, China. During the 16th century, it functioned as a significant hub for international trade despite being officially banned by China's ruling Ming dynasty.
The port served as an illegal entrepôt that attracted traders from Japan, Southeast Asia, and Portugal. Portuguese sources referred to the location as Liampó, a name derived from the nearby mainland city of Ningbo. Shuangyu gained notoriety as a smuggling hub and pirate haven starting as early as 1524.
The port's period of activity ended in 1548 when it was destroyed by the Ming navy. While historical accounts of its destruction were recorded by the 16th-century Portuguese travel writer Fernão Mendes Pinto, his descriptions of the event are considered to be greatly exaggerated.