A new species of Syzygium Gaertn. (Myrtaceae) is described from North East India: Syzygium nivae Barbhuiya, J.Sarma & S.Dey, sp. nov. The new species is a rheophyte, which is restricted to the Kopili riverbed of West Karbi Anglong district of Assam. The present species shows little affinity with Syzygium khasianum (Duthie) N.P.Balakr. in having lanceolate leaves, paniculate inflorescence and calyptrate petals, but differs in various aspects, such as shrubby rheophytic plant habit, narrower leaves, non-caudate leaf apex, shorter peduncles, larger flowers etc.