Zygosaccharomyces rouxii is a highly osmotolerant yeast, closely related to Saccharomyces cerevisiae. The reason for its osmotolerance has not yet been discovered. One of the factors influencing the osmotolerance of a yeast cell is its cell wall. The two mostly studied wild-type Z. rouxii strains, CBS 732 and ATCC 42981, differ in their requirements for the treatment of their cell surfaces before electroporation, which suggests differences in their cell walls. In this paper, the osmotolerant and cell wall properties of the two Z. rouxii strains were studied. Differences in their tolerance to high salt content in the medium, their resistance to lysing enzymes Lyticase and Zymolyase, their cell-wall polymer content and the micromorphology of their cell walls were observed. The effect of a salt stress on the cell wall properties of the two strains was studied. The results obtained suggest that the less osmotolerant CBS 732 strain possesses a more rigid cell wall compared to the more osmotolerant ATCC 42981, whose cell wall seems to be more flexible and elastic.