An electric dust collecting device and an air conditioner having the same are disclosed. The electric dust collecting device includes a first filter unit including a plurality of discharge electrode plates which are spaced apart from each other and have spaces defined therebetween, a high voltage generator electrically connected to all of the plurality of discharge electrode plates, and a second filter unit disposed downstream of the first filter unit in an air flow direction and connected to a ground to cause corona discharge between the discharge electrode plates and the second filter unit, whereby particles electrically charged by corona discharge are collected at the second filter unit. The first filter unit has a simplified structure, and cleaning effect is improved.