The investigation reported in this paper deals with the theoretical study on polar molecule HCN in plasma medium. In the present calculation, the electron- dipole potential is modified and to introduce the screening effects of plasma is characterized by the inverse Debyeshielding length Âï¬Â in a0 -1. The Born Eikonal Series Approximation is used to calculate the differential scattering cross sections (DCS) for low energy the rotational excitation of target Polar molecule HCN, using various values of Âï¬Â. The results obtained are compared with the theoretical calculated Mohanan S., et al results. It is observed that due to the effect of plasma screening, the DCS increases considerably near the forward direction.