To provide a cleaning device for a releasing agent spray cassette which efficiently and securely cleans the inside and the outside of the spray nozzle of a releasing agent spray cassette used for a die casting apparatus, and a method for cleaning a releasing agent spray cassette using the same.

The cleaning device 1 for a releasing agent spray cassette includes: a cleaning tank 90; a releasing agent spray cassette supporting member 10 holding a releasing agent spray cassette 50 freely attachably/detachably and further feeding a pressurized fluid to the inside of the spray nozzle 55 of the releasing agent spray cassette 50; an elevating means of elevating the releasing agent spray cassette supporting member 10, immersing the releasing agent spray cassette 50 into a cleaning solution and pulling up the same from the cleaning solution; a pressurized fluid feeding means of feeding the pressurized fluid to the pressurized fluid feeding chamber; and a bubble jetting means arranged at the inside of the cleaning tank 90 and jetting bubbles toward the spray nozzle 55 immersed into the cleaning tank 90.