Portnyagin (Russian: Портнягин) is a Russian masculine surname derived from the occupation of portnyaga, portnoy, meaning tailor. Its feminine counterpart is Portnyagina. The surname may refer to

• Igor Portnyagin (born 1989), Russian football player
• Paul Portnyagin (1903–1977), Russian Greek-Catholic priest, teacher and orientalist

• All pages with titles containing Portnyagin
• All pages with titles containing Portnyagina
• Pontryagin