本研究探討在證券發行決策中，會計穩健性對於緩和負債與權益代理成本所扮演的角色。本研究將證券發行決策設定為企業在普通股現金增資、普通公司債以及轉換公司債等三種外部融資工具間之選擇，並以台灣非金融業上市櫃公司於2000至2007年期間曾發行前三種融資工具之一者為樣本。實證結果發現，若公司之財務報導較穩健，則其發行轉換公司債取代普通股權益融資之可能性較低；普通股現金增資相較於普通公司債融資之可能性較高；此外，對於具成長機會之公司，發行轉換公司債取代普通公司債融資之可能性較高。本研究亦發現，若公司預期將從事外部融資，會增加其對會計穩健性之需求，尤其將進行普通股融資時。本研究之實證結果支持了會計穩健性在緩和權益市場資訊不對稱所扮演的角色。研究發現會計穩健性與轉換公司債融資所呈現之關係，隱含了該兩種機制對於緩和過度投資之代理衝突具有替代關係，對於緩和具成長機會公司之投資不足問題，則存在互補關係。

In this study, I examine the role of accounting conservatism in mitigating debt- and equity-related agency costs in the context of security issue decision. The security issue decision is formulated as the choice among three external financing alternatives, including common equity, straight bonds and convertible bonds. By collecting a sample consisted of Taiwan listed nonfinancial firms that raising external capital during the period from 2000 to 2007, I find that more conservative financial reporting decreases the likelihood of issuing convertible bonds to substitute for common equity and increases the likelihood of issuing common equity instead of straight bonds. Besides, for those firms with growth options, more conservative financial reporting increases the likelihood of issuing convertible bonds to substitute for straight bonds. I also find that, anticipating the security offering generates incremental demands for accounting conservatism during the period preceding the security offering, particularly for common equity issuers. The evidence in this paper supports the role of accounting conservatism in mitigating information asymmetry in the equity market. The documented association between accounting conservatism and convertible bond financing implies that these two mechanisms constitute substitutes in mitigating over-investment or managerial discretion but serve as complements in ameliorating risk shifting or under-investment for firms with growth options.