A cast iron skillet can be used on a glass-top stove, but there are a few things to keep in mind. First, make sure the bottom of the skillet is smooth and clean. If it's not, it could scratch the surface of the stove. Second, use a lower heat setting than you would with other types of cookware, as cast iron can retain heat longer and cause damage to the glass top. Finally, always lift the skillet when moving it around on the stovetop; don't slide it, as that could also scratch the surface. With these tips in mind, you can enjoy all the benefits of cooking with a cast iron skillet on your glass-top stove.