International accounting standards require, in particular the impairment of (36) asset value standard No (31), re- evaluation of assets to display the value of fair value as the replacement value at the end of the period or fiscal year of the disclosure of assets, real value, the represent philosophy of accounting to relevant of different models to call the fair values, especially in case of using methodology - based pricing capital asset model. The researcher presented a model for measuring the impairment of the book value of assets form, which contributes to the measurement of accuracy of the fixed measurement of accounting income and taxable income help guide the preparation of financial statements in the presentation of fixed assets as fast as they converge with the fact that revenue and economic benefits of the asset in the financial period is ending. Because the accounting incases always different on taxable income for the application of the income tax act, although the act, to impose tax in net profit, which present the income statement prepared in accordance with the Egyptian accounting standards, but on grounds of maintaining the public revenues of ministerial decisions were issued contrary to that application and became the standard (31) can’t be applied when determining the tax base. Which led to a loss in its submission for income tax, which is a clear challenge, there is no application of some financial standards, which is what the researcher tried to show. He presented it to determine the tax impact of not applying the standard.