This paper studies the quality of mandatory financial forecasts which announced by Taiwan lists and OTC companies ¡]hereinafter called ¡§the companies¡¨¡^. Does outside financial analyst can offer the public users more useful financial forecast than the companies¡H What¡¦s the difference on precision between financial forecasts issued from the companies and outside analysts¡HBesides, this paper also tests if the companies would perform earnings management for meeting the public expectation. The empirical results indicate that for public investors, the mandatory financial forecasts issued by the companies didn¡¦t show better accrual precision than the financial forecast issued by outside analysts. There wasn¡¦t any significant difference on degree of differential between financial forecast prepared by outside analysts and the companies. The risk for using both of the financial forecasts are the same. That means the investors can rely on none of the companies and outside analysts¡¦ forecasts to do investment decision. And the companies performed earning management to meet the consistent expectation of earning arose from market which can avoid the bad result when the actual financial report differ from forecast. In summary, the mandatory financial forecasts in Taiwan can not offer timely useful information to investors. Most of them only increase the preparation cost and control cost. Some of the companies even use them as the tool to collect money from public for personal welfare. We recommend the government authorities to consider the benefit of voluntary financial forecast system in UAS when they are reviewing the mandatory financial forecast system. The voluntary financial forecast system may solve the problems of incomplete predictability of financial forecast and asymmetry of information, finally increase the usefulness of financial forecasts.