Banks issue subordinated debt in order to reduce lending risk, however, is there any significant improvement in banks’ capital structure after the issuance? We select 10 local banks in Taiwan as sampling and use Fama-French 3-factor model and Cumulative Average Abnormal Return to evaluate the short-term effect in stock return. After that, the purpose of this study is to provide a comprehensively empirical review on the local regulatory, issuing condition, banks’ capital structure and asset quality and try to find out the correlation among each factor as aforementioned.