Abstract: An electrostatic precipitator comprising a corona discharging section for charging dust particles as they pass through and a dust collecting section which has at least two sets of negative plate electrodes for collecting the positively charged dust particles and auxiliary plate electrodes to accelerate the dust particles to the collecting plate electrodes. The collecting and auxiliary plate electrodes in each set are so alternately arranged that the arrangement of the collecting and auxiliary plate electrodes in one set is opposite to that in the adjacent sets whereby the positively charged dust particles passing through the dust collecting section can be effectively collected to the collecting plate electrodes to improve collecting efficiency and energy efficiency with mimized noise.