臺灣金管會為提升銀行競爭力並與國際接軌，業於2025年開始實施巴塞爾資本協定三，並提前開放銀行申請採內部評等法計提資本。鑑此，本文利用情境模擬的方式，檢視於內部評等法下，倘授信資產分佈變動，對銀行風險性資產(RWA)及資本適足率(CAR)產生的影響為何。依試算結果顯示，於「經濟衰退情境」下，風險性資產將較原「正常情境」大幅上升，並造成銀行的資本適足率大幅下降。此外，經不同情境的試算結果發現，內部評等法因採多項細緻的風險參數，相較標準法而言，將更能貼切的反應銀行資產品質的真實情況，應能有效提升銀行內部的風險意識，促使銀行完善風險管控，邁向穩健及永續營運的目標前進。

To enhance banking competitiveness and align with international standards, Taiwan’s Financial Supervisory Commission (FSC) implemented Basel III in 2025 and allowed banks to apply for the Internal Ratings-Based (IRB) approach. This study uses scenario analysis to examine how changes in credit asset allocation under the IRB approach affect Risk-Weighted Assets (RWA) and the Capital Adequacy Ratio (CAR).The results show that under an economic downturn scenario, RWAs increase significantly, leading to a notable decline in CAR. Compared with the Standardized Approach, the IRB approach more accurately reflects asset quality through granular risk parameters, thereby strengthening banks’ risk awareness and supporting stable and sustainable operations.

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