Five South American species of Sarcocornia (Chenopodiaceae) are accepted, four of which are new combinations in that genus: S. ambigua (Michx.) M.A. Alonso & M.B. Crespo, S. andina (Phil.) Freitag, M.A. Alonso & M.B. Crespo, S. magellanica (Phil.) M.A. Alonso & M.B. Crespo, and S. neei (Lag.) M.A. Alonso & M.B. Crespo. Synonyms and types arc cited for the accepted taxa, and three lectotypes, an epitype and a neotype are designated to establish a correct usage of the names. Main diagnostic characters, ecological features and distributions are also reported for each taxon, and a key is provided to facilitate identification.