違約金，係由契約當事人所約定，作為債務人債務不履行時應對債權人所為之給付。勞動契約之違約金條款在我國司法實務只會受到法院的低度審查，當事人擁有高度之契約自治。然則，勞動契約中得否約定違約金條款並非毫無疑義，亦非任何國家之法令均允許如此作法，日本勞基法即禁止勞動契約中締結違約金條款。本文初步研究後認為，在不論及修法之前提下，只能嘗試將勞動關係中之違約金類型化，並建立基本之解釋原則，始能解決目前違約金被過度使用於勞動關係之情況。本文將勞動關係中之違約金區分為「債務不履行」、「侵權行為」、「違反工作紀律」之違約金，其中前者不應約定懲罰性違約金條款，以免雇主因勞工之違約行為反而有獲利之結果。此外，本文亦認為，下級審法院於審理勞動關係中違約金爭議時，就違約金之數額是否過高、應否酌減乙節，應遵循最高法院晚近之見解，採取職權調查方式加以確認，以免勞工負擔過重之舉證責任。

Liquidated damages and penalty clause （the “CLAUSE” same below ） is an agreement between both parties of contract as the compensation for creditor when debtor violates the contract. Taiwanese courts apply the curtailed strict scrutiny for the CLAUSE disputes concerning employment contract, hence both parties of employment contract have high autonomy when exercising such CLAUSE under the principle of freedom of contract. However, the CLAUSE in employment contract is not indisputable, as many countries prohibit the agreement on the CLAUSE in employment contract as exemplified in the Labor Standard Act of Japan. This article argues that, under the premise that the related regulations remain unchanged, the only approach to prevent the abuse of the CLAUSE in employment contract is to classify the type of the CLAUSE, and create rules of interpretation. Accordingly, this article classifies the CLAUSE into three types: violation of contract, infringement, and violation of discipline in workplace. For the first one, the penalty shall be prohibited for preventing the unjust profit of an employer due to employees’ breaching of contract. Further, it is suggested that when adjudicating on liquidated damages of an employment contract, lower courts shall follow the Supreme Court’s latest opinion by taking inquisitive investigation to affirm the reduction of burden of proof by employees.