A glass substrate and a method for manufacturing the glass substrate are provided. The glass substrate may include a base glass including SiO2, Al2O3, and Li2O, and nanocrystals having an average diameter in a range from about 5 nm to about 10 nm, thereby exhibiting enhanced surface strength properties while maintaining good transmittance properties. The method may include a step of heat-treating a base glass, thereby providing a glass substrate having enhanced strength properties.