Discovery of pulsars included in binary systems (BS) is dated to 1974, when Hulse and Taylor announced the parameters of pulsar PSR B 1913+16. It inspires great motivations for possible new physical measurements of the properties of neutron stars (NSs). We present a simple model to estimate the deformation in shape of two neutron stars bounded to each other in a binary system due to their mutual gravity. The model predicts the Bulk modulus of the pulsar – as an infinite nuclear matter. In particular, the model determines the stress and the strain of a pulsar included in PSR B 1913+16 binary system within the frame of Newtonian theory of gravity. The calculations show that, our approach is consistent with the model of two spherical neutron stars up to the eccentricity-squared. The model could evaluate the axial elongation of the observed NS as well as the eccentricity. The eccentricity is found to be of order 10^(-5) and the elongation is of the order 10^(-9) km.