Corona discharge introduces polar groups into the polymeric surfaces and, as a consequence, improves the surface energy, wettability, and adhesion characteristics. The main chemical mechanism of corona treatment is oxidation. This article further discusses some special problems that are related to corona treatment of polyolefin films by reviewing the recent developments in this field, such as effect of corona treatment on adhesion, effect of resin additives on corona treatment, insufficient treatment and over-treatment of corona discharge, aging, and re-treatment.