This study is intended to order and classify countries based on the degree of conservatism of their accounting standards and practices. We explain the results in terms of natural, economical, information, political, social, and legal factors. We define that the conservative accounting procedure is the one by which current term's net profit is appropriated in the direction of understatement on an assumption of inflationary trend. The established accounting standards or individual firm's attitude in selecting accounting alternatives determine the degree of conservatism of accounting standards and accounting practices of each country. Such accounting standards of firm's attitudes are considered to be determined by the natural, economical, information, political and legal environment. We apply Multiple Regression Analysis for determination of the relation between the degree of accounting conservatism and the above factors, and Cluster Analysis for classfication of countries. Data are taken from the survey of accounting principles and reporting practices for 64 countries conducted by the Price Waterhouse International.