Siyayyar Alaska ita ce siyan Alaska da Amurka ta yi daga Daular Rasha.An tura Alaska a hukumance zuwa Amurka a ranar 18 ga Oktoba, 1867, ta hanyar wata yarjejeniya da Majalisar Dattijan Amurka ta amince.Rasha ta kafa kasancewarta a Arewacin Amurka a farkon rabin farkon karni na 18, amma 'yan Rasha kaɗan ne suka taɓa zama a Alaska.Bayan yakin Crimean , Tsar Alexander II na Rasha ya fara nazarin yiwuwar sayar da Alaska, wanda zai yi wuya a kare shi a kowane yaki na gaba daga cin nasara da babban abokin hamayyar Rasha, Birtaniya.Bayan kawo karshen yakin basasar Amurka , sakataren harkokin wajen Amurka William Seward ya shiga tattaunawa da ministan Rasha Eduard de Stoeckl domin siyan Alaska.Seward da Stoeckl sun amince da wata yarjejeniya a ranar 30 ga Maris, 1867, kuma Majalisar Dattijan Amurka ta amince da yarjejeniyar ta wani yanki mai fadi.Sayen ya kara da fadin murabba'in mil 586,412 (1,518,800 km2) na sabon yanki zuwa Amurka kan farashin dala miliyan 7.2 1867.A cikin sharuddan zamani, farashin ya yi daidai da dala miliyan 133 a cikin dala 2020 ko $0.37 a kowace kadada.