Nowadays, Low density polyethylene (LDPE) is increasingly used as voltage cable insulating material. Owing to its excellent mechanical and electri-cal properties, LDPE may undergo degradation under service conditions. The focus of this work is to investigate the eventual impact of temperature on the LDPE characteristics. For this purpose, dielectric properties (Breakdown strength, Dielectric loss factor and dielectric constant); and mechanical charac-teristics (tensile strength and elongation at break) were studied. Aim of this work is the investigation of possible changes in some Low density polyethylene (LDPE) properties subjected to thermal constraint. The obtained results show that all the properties are widely affected by thermal constraint.