To provide a method of processing a tempered glass in which a length of time required for manufacturing one plate of a product glass is significantly reduced while the quality of the product glass is secured. In the method of processing the tempered glass in which a stacked block (1a) acting as a chemical tempered glass (1) is processed by using a processing device (8) under a condition that the processing device (8) is rotated and vibrated, the stacked block (1a) is cut out from a stack (1A) acting as the chemical tempered glass (1) by using a dicing blade (84), prior to the processing of the stacked block (1a) by using the processing device (8), and a finishing to an outer periphery of the stacked block (1a) is also performed during the processing of the stacked block (1a) by using the processing device (8).