To provide an LED display device capable of preventing mis-operation of a driving circuit by reducing a spike noise generated on a power source line at the switching time between the ON and OFF states of LED's, capable of reducing also a radiation noise, and capable of fitting to a legal regulation concerning EMC by also reducing a radiation noise.

This device is equipped with a display part board 2 on which many LED's 2a of each pixel unit facing to the front are arranged, and a circuit part board 3 on which circuit parts arranged on the back side of the display part board 2 at intervals, and conductive to the LED's 2a, are formed. The circuit part is equipped with a power source connector 5 connected to an external power source, a main capacitor 6 arranged near the power source connector 5, and one or more sub-capacitors 7, 8, 9 arranged on the end of a conduction path to the LED's 2a, and a noise voltage in the circuit is smoothed by charge and discharge actions of the main capacitor 6 and the sub-capacitors 7, 8, 9.