本研究使用台灣的營利事業所得稅資料並且以托賓自我選擇模型來檢視租稅逃漏、稅務選查與會計師稅務簽證三者的關聯性。實證結果顯示台灣的稅務機關在查核預算的限制之下會進行有系統的稅務選查程序；進一步來說，使用會計師稅務簽證的企業組織較不易被稅務機關選查。此外，企業組織的重要特徵如規模、財務狀況、獲利能力以及會計師稅務簽證的使用與否將會影響企業組織的租稅逃漏額。最後，我們發現會計師稅務簽證的使用對於租稅逃漏的影響會隨著公司的規模大小而改變，營收大於一億的企業組織若使用會計師稅務簽證將會比未使用會計師稅務簽證的企業組織有更高的逃漏稅額。因此，我們認為與會計師稅務簽證相關的政策法規可能需要重新評估是否適切。 / This study uses the business income tax dada in Taiwan to empirically examine the relationships between audit selection, tax evasion, and the usage of CPA-attestation. Tobit model with self-selection is used in this study. Empirical results provide evidence that tax agencies in Taiwan employ a systematic audit selection process, subject to the constraints of audit budgets. Additionally, firms using CPA-attestation are less likely to be selected for audit. The results also provide evidence that some important characteristics of firms, such as size, financial position, profitability, and the usage of CPA-attestation, may influence the amount of tax evasion. Finally, we find that the effect of CPA-attestation on tax evasion may vary with different sizes of firms using CPA-attestation. Hence, the policy and tax regulations associated with the usage of CPA-attestation may need to be re-evaluated.