The effect of gamma-irradiation on the molecular mass distribution and solubility of low-density polyethylene (LDPE) in dependence of samples＇ thickness, irradiation intensity and dose have been investigated by the methods of turbidimetry and gelation measuring. Irradiation took place in the presence of air. It was shown that the destruction and crosslinking processes proceed simultaneously with the irradiation. The expressiveness of these processes depends on the irradiation intensity, dose and samples＇ thickness. Also, the decrease of gel point occurrence and difference in velocities of degradation and crosslinking of macromolecules were established along with the decrease of the samples＇ thickness and irradiation intensity.