We have isolated and characterized transcripts for two major intrinsic proteins (MIPs), AnNIP1;1 and AnNIP1;2, from salt stressed roots of the halophyte Atriplex nummularia. Conserved amino acids and phylogenetic analysis of these MIPs clusters them into the plant nodulin-like intrinsic protein (NIP) subgroup. Functional characterization by heterologous expression of both proteins in yeast confirmed their capacity to transport glycerol. fps1Δ Yeast mutants expressing functional AnNIP1;1 and AnNIP1;2 showed increased glycerol uptake, and intra- and extracellular glycerol contents in agreement with their glycerol permease activity. Proper functional expression of AnNIP proteins in yeast needed the removal of the unique hydrophilic N-terminal domain of both proteins, which did not show to be necessary for their transport activities.