Face value refers to par value. Both terms are synonymous. Par value is the value below which a stock cannot be legally issued upon its initial public offering. This amount is usually a small negligent amount. However, par value has now become an outdated concept and some stock are now issued with this preset amount. Of course this varies by state depending on the laws. In addition, par value is used in accounting to record the nominal value of total share outstanding in the balance sheet.
In reference to bonds the term has a different meaning. In this case Face Value refers to the principal that must be paid at maturity date.