Abstract: Blends specimes consist of polyethylene reinforced with different ratio of polypropylene (5, 10 and 15%) is prepared in this study. The effect of different concentration of citric acid on mechanical and physical properties of these polymeric blends specimens such as maximum tensile strength, maximum deformation, impact energy, hardness and electical conductivity is investigated in current study. The blends specimens are tested after immersed for 30 days in citric acid with concentration of 5, 10 or 20%. The obtained results showed that the reinforcement by polypropylene improve the maximum tensile strength and hardness properties while reducing to some extent the maximum deformation, impact energy and electrical cnductivity properties. Citric acid played the role of plasticizer and led to a relative increase in maximum tensile strength, maximum deformation, impact energy and electrical conductivity while led to a slight decrease in hardness of blends specimens.