Domain miâ hē-thóng (Eng-gí: Domain Name System), kán-chheng DNS, sī Internet ê chi̍t ê ho̍k-bū (service), sī chi̍t ê chong domain miâ kap IP tē-chí hō͘-siong siá-siōng (写像) ê hun-soàⁿ database. Iōng DNS ū-hoat-tō͘ hong-piān ê chiūⁿ-bāng. DNS iōng kàu TCP kap UDP ê port 53.