In this paper methods of dust cake removal from collecting plates in electrostatic precipitators are presented. If dust cake removal from the collecting plates surface is not enough, the dust collection effectivity decreases. Some methods of dust cake removal from collecting plates are known: electromagnetic method, pneumatic method, acoustic method, plushing and mechanical rapping. The most effective and the most often used method of removal of dust cake, which is accumulated on the collecting plates in dry electrostatic precipitators, is mechanical flicking off method. Mechanism of action by using this method depends on the serial inducing of vibrates by hitting of special hammers on the collecting plates.