The main difference is that while not in use, the bedspread covers the bedding and the mattress.
Bedspread and bedsheets are two sorts of bedding that can be employed for making a beautiful bedroom. A bedspread is a beautiful roof that usually covers the whole bed. Bed linen is placed under the cover, just above the mattress. Bedsheets are generally useful, but a bedspread is not only functional but also attractive.