Public companies which issue securities are required to disclose the audit fees when the initial audit fees of succeeding audit firms discounted since 2002. The authorities want to let financial statements users realize whether the audit fees paid to audit firms are deficient or not and make them actively concern and watch over the earnings quality of financial statement. The result of this study indicates that the investors' perception to lower earnings quality is obvious when the initial audit fees paid to succeeding audit firm are discounted following the audit firm changes from one big audit firm to another big audit firm. Besides, the more directors and supervisors are controlled by controlling shareholders, the more reduction of investors' confidence in earnings quality of financial statement.