This study was carried out at the tissue culture lab, Horticulture Department, Faculty of Agriculture, Minia University, Minia, Egypt. under in vitro condition to screening the response of four potato varieties (Diamond; Burren; Maritiema and Lady Balfour) to water stress induced by adding sorbitol in the culture medium. Four concentrations of sorbitol (0.0, 0.1, 0.2 and 0.3 mole /liter), in Murashige-Skoog (MS) medium were used for exerting the water deficiency stress on the plantlets with three replications, in completely randomized design. Data revealed that the potato cultivars were significant differed for plantlet height, number of leaves per plantlet,  number of nodes per plantlet, number of roots per plantlet and plantlet weight  in the medium without sorbitol. Moreover, different response of potato cultivars was observed to various levels of sorbitol concentrations. Increasing the concentration of sorbitol lead to significant decreased in all studied traits, as compared with control treatment (sorbitol free). However, the most reduction of morphological parameters was observed in Maritiema and Lady Balfour cultivars, and considered as susceptible cultivars for water deficit. These results indicated also that the Diamond variety is a drought-tolerant than the other potato cultivars which used in the current study. These results indicated that the simulation of drought stress under in vitro conditions during the regeneration process constitutes a convenient way to study the effects of drought on potato responses. In-vitro this technique was shown to be useful in identifying relatively drought-tolerant genotypes at early stages of development and this can be a very useful tool for screening large number of varieties or breeding lines of genotypes within a short time.