The present study concentrates on the influence of structural parameters of potato tuber tissue on its mechanical properties. Observations of the cell structure were carried out by an optical confocal microscope. Image analysis allowed obtaining parameters describing cell size and cell shape. Image analysis and compression test of the outer core of three potato varieties: Danusia, Kuba, Triada were carried out. Stress-strain curves were recorded in tests with constant rate 5 mm min-1. It was found out that the parameters of the structure such as: cell area and cell perimeter, exert a significant influence on mechanical parameters, i.e., strength and modulus of elasticity. The present study did not confirm that there is a relation between cell shape and the mechanical parameters.