本文從民法法律行為之基本理論出發，說法律行為的本質，將股東會、董事會決議行為之瑕疵態樣及其效果，配合決議行為之一般成立要件、特別成立要件及一般生效要件、特別生效要件來做一整理，希冀能藉此以符合我國民商合一之法制。 股東會決議行為在何種情形之下始可構成股東會決議，在承認私法自治的前提下，股東會決議只要能符合其本質上之特別成立要件，當可合法生股東會決議之效力，不過實際上在現行的各國公司法中，或多或少的都會對公司法人的股東會加以規範，但基於憲法保障人民財產權及自由權的意旨，國家介入私法之行為須有正當理由，在一般商業行為而無涉公共利益時，更應限縮國家可使用的手段，以期符合憲法第二十三條之比例原則。在公司的股東會決議有不符合法定的「特別生效要件」時，該法律行為本應為無效，但是為了緩和法律適用的嚴酷性，以及尊重私法自治的原則，公司法第一百入十九條即明文規定，股東會之召集程序或決議方法，有違反法令時，不使其為當然無效而是僅為得撤銷，與民法第七十三條的一般原則並不相同。而從此亦可得出，股東會決議若是欠缺其本質上所必須的「特別成立要件」者，並非在公司法第一百八十九條所規定涵攝範圍內，法律上之評價自不應僅為「得撤銷」，而應回歸到民法的基本理論：欠缺特別成立要件時，該法律行為不能有效成立，故該股東會決議應屬當然無效，無待撤銷。因此欠缺特別成立要件和特別生效要件之股東會決議的效果，在法律上的評價自有不同，是何者始應屬於股東會決議之「特別生效要件」；何者又屬於股東會決議之「特別成立要件」即有區分之必要及實益。 又關於董事會決議瑕疵之效力，由於公司法並無相關規定，依學說及實務之見解，認為董事會無論因決議內容或決議方式違法而具有瑕疵時，利害關係人得隨時以任何方法主張其為無效，並無第一百八十九條之準用。若此，則當有瑕疵之董事會決議為無效時，董事長依該無效之董事會決議所為之行為，其效力究應如何強能周全的保障第三人之權益，則不無疑異。本文於此亦就現行法及實務見解作類型化之整理，以俾供參考。

Setting forth on the basis of fundamental theories under civil juristic conduct, this paper aims to examine all forms of defectiveness and its effectiveness of resolution by shareholders' meeting or board of directors in a company limited by shares, i.e., from the essence of juristic conduct to review and analyze the forms of general and special requisites of formation as well as general and special requisites of effectuation under our legal system that codifies general principles of commercial law into the Civil Code. Under the principle of party's autonomy, a resolution conduct of shareholders' meeting will constitute a resolution of shareholders' meeting as long as such resolution conduct confirms to the nature of special requisite of formation. In the event that shareholders' resolution is in violation of any special requisite of effectuation prescribed under the law or ordinance, such juristic conduct should be invalidated; yet, to ease the hardship of said application of law and pay respects to autonomy principle, Article 189 of the Company Law stipulates that in case the procedure for convening a shareholders' meeting or the method of resolution does not conform to any law or ordinance or the company's articles of incorporation, such shareholders' resolution is only avoidable, which differs from the general principle laid out under Article 73 of the Civil Code. Accordingly, if such shareholders' resolution lacks of the special requisite of formation, required by its nature, this is not covered by the foregoing Article 189, and shall restore back to the basic theories of civil law; that is, a shareholders' resolution lacking the special requisite of formation shall be null and void since said juristic conduct cannot be formed. Therefore, it is essential to distinguish between special requisite of formation and special requisites of effectuation. In terms of the effectiveness of a defective resolution by a meeting of board of directors, our Company Law is silent in this regard. Pursuant to academic theories and court practice, it is settled that in case the procedure or substance of a resolution adopted at a meeting of board of directors is contrary to law or ordinance, the said resolution shall be null and void; that is, Article 189 is not applicable under such circumstance. One question remained is whether the conduct performed by the president that executes the board resolution, announced null and void, is effective in balancing the protection of rights and interests of the third party. This paper further puts in order by categorizing the various forms among the prevailing law and court practice in hope to explore feasible solutions to unrest issues.