Effective applicability of composite materials in towers for high voltage overhead transmission lines is a question of present interest. According to the conventional opinion, primary benefits of composite towers are specified by lightweight and compact size of composite modules. Significantly, that electrical insulating properties of composite towers can be used for more efficiency of constructions. This article focuses upon findings of lightning protection and insulation for 220 kV overhead transmission line with the lightening conductor and electric insulating towers. It is shown that by using insulating properties of composite towers it is possible to decrease dimensions of 220 kV line and increase its operational reliability.