Shuinsen; or 'Red Seal ships'; were Japanese armed merchant sailing ships bound for Southeast Asian ports with a red-sealed patent issued by the early Tokugawa shogunate in the first half of the 17th century. Between 1600 and 1635; more than 350 Japanese ships went overseas under this permit system.

Japanese merchants mainly exported silver; diamonds; copper; swords and other artifacts; and imported Chinese silk as well as some Southeast Asian products (like sugar and deer skins). Pepper and spices were rarely imported into Japan; where people did not eat a great deal of meat due to the local preponderance of adherents to the Buddhist belief system. Southeast Asian ports provided meeting places for Japanese and Chinese ships.

In 1635; the Tokugawa shogunate; fearful of Christian influence; prohibited Japanese nationals from overseas travel; thus ending the period of red-seal trade. This measure was tacitly approved of by Europeans; especially the Dutch East India Company; who saw their competition reduced.