The present investigation deals with the mechanical, thermal and rheological properties of binary HDPE/EPR blends at various dispersed phase (EPR) concentrations. The effects of EPR concentration on tensile, impact properties of the pure HDPE and HDPE/ EPR blends were studied. Analysis of the tensile data in terms of various theoretical models revealed the variation of stress concentration effect with blend composition. Rheological study was carried out to investigate the change in viscosity with shear rate. DSC results show decrease in percent crystallinity of HDPE upon incorporation of EPR except at 20wt% rubber concentrations wherein the percent crystallinity has shown marginal increment. © Taylor & Francis Group, LLC.