The present invention relates to a method for cutting of bonded substrate, when the bonded substrate is under a scribing process, it can not only remove the useless and virtually disposed portion of the substrate formed with the tightly sealed portion to make it narrow to maximum limit, but also make the cutting surface smoothly carry out the cutting. The cutting method used on the bonded substrate (10) carrying out the cutting on the tightly sealed portion (8) formed in between the upper glass portion (11a) and the lower glass portion (11b) of the bonded substrate (10) comprises the following stages: irradiating laser towards the position of the tightly sealed portion (20) contacting to at least one of the upper glass portion (11a) and the lower glass portion (11b) to form the cutting lines (13a, 13b) on the inner surface side of at least one of the upper glass portion (11a) and the lower glass portion (11b); and utilizing the scribing wheel (70) to carry out the scribe line along the cutting lines (13a, 13b) towards at least one of the upper glass portion (11a) and the lower glass portion (11b), thereby having the efficacy in being able to form the elegant cutting surface.