It has been studied the behavior of temperature dependence of volume electroconductivity σ on direct current (DC) of composite medium of high-density polyethylene/α-Fe 2 O 3 in the field of T=20-135 0 C within heating-cooling conditions before and after γ-irradiation at dose up to 500kGy. At lgσ(T) dependence of unirradiated composites while heating at low and high temperatures besides linear sections, it is observed the region of sharp decrease at 50-80 0 C, associated with dipole orientation processes of adsorbed water molecules. At lgσ(T) dependence of composite samples irradiated at D=100kGy there is not any region of sharp decrease σ. It is shown that after γ-irradiation by dose D=500kGy the second maximum appears on the curve of forward trace of the composite HDPE+ 10%α-Fe 2 O 3 at T=80 0 C, which can be the result of change in the state of quasi-Fermi level. Behavior of lgσ(T) function at heating-cooling is explained by the "asymmetry" effect of electrically active defects. It is shown that the increase in volume conductivity after γ-irradiation is weakly expressed.