The invention relates to the technical field of combustors, in particular to an ignition device of a combustor. The ignition device is sequentially provided with a fuel conveying device, a fuel nozzle, a flame stabilizing disc and an ignition mechanism in the combustion supporting air flowing direction at the tail end of an air supply cylinder. The flame stabilizing disc is provided with multiple oblique grooves, and a rotational flow area is generated after the combustion supporting air passes through the oblique grooves. The ignition mechanism is located at the position, on the downstream part of the flame stabilizing disc, in the rotational flow area and is deflected from the position of the center line of the fuel nozzle. The ignition device is scientific and reasonable in structural design, and the problems that in an existing ignition method, the ignition success rate is not high, the ignition time is long and the power needed for ignition is large are solved. The rotational flow area is generated by the combustion supporting air through the oblique grooves of the flame stabilizing disc, and the combustion supporting air is mixed with fuel injected by the nozzle in the position, on the downstream part of the flame stabilizing disc, of the rotational flow area, the mixture is ignited through the ignition mechanism to form stable flames, and continuous and stable combustion of the combustor is ensured. The ignition success rate is greatly increased, the ignition time is shortened, and the ignition power is also greatly reduced.