A glass substrate excellent in strength properties and a glass cutting method are provided. When a glass substrate having predetermined size is to be formed by cutting a glass plate, any crack or chip is not generated on a cut face. Therefore, a pulverized powder is prevented from being generated from this portion. A glass substrate is obtained by cutting at least with laser light radiation so that a surface roughness of cut side faces and of the glass substrate are 50 nm or less and a depth of laser marks and on the cut side faces are 0.06 mm or more.