A cooking appliance including a cleaning environment provided to be able to easily remove contaminants inside the cooking appliance by heating the inside of a cooking room to a temperature for amorphization of the contaminants, and method for controlling the same. The cooking appliance includes a main body configured to have a cooking room; a steam generator configured to supply steam to the cooking room; a water supplier arranged in the main body and configured to store water; and a pump assembly configured to supply water to the steam generator and the cooking room from the water supplier.