The hyperhydricity in eggplant (Solanum melongena L.) plants was monitored by the induction of the ER-luminal resident protein BiP. Although tissue culture conditions may induce BiP synthesis, the accumulation of BiP in hyperhydric shoots was consistently higher than in non-hyperhydric shoots. The leaf and stem anatomy in non-hyperhydric and hyperhydric eggplant was investigated aiming to identify structural changes associated with this phenomenon. In non-hyperhydric organs there were smaller and more organized cells, besides a more differentiated vascular system when compared with its hyperhydric counterpart. Scanning electron microscopy of leaves showed that leaf surface and stomata differentiation were also affected in hyperhydric plants.