Aiming to focus the protective role of the sugar trehalose under oxidative conditions, two sets of Saccharomyces cerevisiae strains, having different profiles of trehalose synthesis, were used. Cells were treated either with a 10% trehalose solution or with a heat treatment (which leads to trehalose accumulation) and then exposed either to menadione (a source of superoxide) or to tert-butylhydroperoxide (TBOOH). According to our results, trehalose markedly increased viability upon exposure to menadione stress, which seems to be correlated with decrease in lipid peroxidation levels. The protective effect of trehalose against oxidative damage produced by menadione was especially efficient under SOD1 deficiency. On the other hand, this sugar does not seem to participate of the mechanism of acquisition of tolerance against TBOOH, since trehalose pretreatment (addition of external trehalose) was not capable of increase cell survival. Therefore, trehalose plays a role in protecting cells, especially membranes, from oxidative injuries. However, this mechanism of defense is dependent on the type of oxidative stress to which cells are submitted.