There is provided a master glass having a structure capable of preventing damage caused by static electricity. The master glass is a substrate on which a deposition process is experimentally performed by being experimentally loaded loading the master glass into a deposition apparatus before starting the deposition process of the substrate for electronic devices. In one embodiment, a master glass includes first conductive patterns and a second conductive pattern. The first conductive patterns are formed to correspond to a deposition pattern required in a substrate for electronic devices. The second conductive pattern electrically connects all the first conductive patterns to one another.