According to the analysis, Tax expenditures in the 2008 tax changes plan does not well correspond to the roadmap of tax policy, broad tax base, low tax rate. This paper points out that both the number of tax expenditure items and their total revenue losses, which increase tax expenditures as creating or renewing the sunset, are a lot more than revenue gained from ending or reducing in the 2008 Tax Changes Plan. A recent trend of increase in tax expenditures is the most likely to violate ''the Rule of a National Tax Reduction Rate Limit'' in the National Finance Act. This paper makes point that the administration should assess each item of dominant expenditure in respect of revenue losses and submit the assessment results to the National Assembly on a recurring basis. Lastly, it suggests that it is necessary to adopt “the Rule of Expenditure Limit'' to comprehend both direct expenditures and tax expenditures.