向來認為確定給付判決之執行力客觀範圍等同於既判力客觀範圍，而未充分說明其根據何在。惟既判力既係於司法領域之內部，在後訴就經判決公權判斷之事項再次為判斷時，要求維持同一之判斷結構及結論，藉以確保法的安定性者，而執行力則係將判決所命給付之內容予以強制現實化之作用，受合目的性之理念所指導者。既判力與執行力兩制度之旨趣及作用既不相同，彼此之客觀範圍即可能有所不同。本文以現行強制執行法所規定及執行實務所承認之數種事件類型為例予以論證，在以確定判決作為執行名義之情形，其執行力之客觀範圍無須恆與既判力之客觀範圍一致。此係因執行力之作用乃強制性實現執行名義所命實現之給付利益，只要具備下列之實體上及程序上正當性，即可擴張其執行力所及之範圍，以有效達成執行目的。亦即，①依執行名義所確定之給付請求權，及該執行名義成立前、後之舊或新事態來看，債權人對於債務人之新給付請求權（被擴張之權利）存在蓋然性很高，且兩請求權實現之實體利益類同，均係執行名義所容認之執行利益；②上開新給付請求權，如非從原執行名義所能明確認定，執行法院尚須依債權人所提事證資料加以審查認定，惟其審認結果並未具實質確定力，債務人對之如有實體上爭執，仍得起訴以資解決；③此項執行名義之流用，固係為發揮其解決紛爭之最大效用，而保護債權人之程序利益及維持訴訟經濟，亦因在與債務人之關係上，尚無須要求或不可期待債權人就該新給付請求權一併或另行取得執行名義，故省略新執行名義之取得，對於債務人並無不公平之處。何況，如債務人對於該新權利之存在亦不爭執，此項省略亦可節省其勞力、時間、費用上支出，而避免蒙受程序上不利益。

The objective scope of enforcement of payment judgment is thought to be equal to the objective scope of res judicata, but the foundation isn't well illustrated. Nevertheless, res judicata is the demand in the interior of judicial domain to hold the same decision when re-deciding in later litigation for law stability. In contrast, enforcement force realizes the judgment by a strong hand and is guided with proper intention. Since the purposed and functions are different between res judicata and enforcement, the objective scopes are probably disparate. This article takes some types of cases ruled by Compulsory Enforcement Law and admitted by enforcement practice for exampled to assert that in circumstances of taking final and unappealable judgment as a ground for execution, the objective scope of enforcement isn't always equal to res judicata. It's because that the function of enforcement force is to compulsory realize the payment interests in grounds for execution. To achieving the purpose of enforcement, the extension of scope of enforcement force is allowable as long as possessing the following legitimacy of substantiality and procedure. 1. From observing payment claim confirmed by grounds for execution and the circumstances before or after the establishment of grounds for execution, the possibility of existence of the creditor's new payment claim (extended claim) is high, and the substantial interests of both claims is similarly the enforcement interests which grounds for execution allow; 2. if the new claim above can't clearly be affirmed by original grounds for execution, enforcement court should examine it through the materials addressed by the creditor. Nevertheless, there isn't substantial determining force in the result of examination, and the debtor still can sue for settling substantial disputes. 3. The mutual use of grounds for execution is to achieve the best effectiveness for settling disputes and protect the creditor's procedural interests and lawsuit economy. Because it has no need to demand the creditor to get new grounds for execution for new payment claim, the saving of new one isn't unfair to the debtor. Furthermore, if the debtor doesn't disagree to the existence of new claim, the saving can economize the expense of effort, time and money, and avoid the procedural disadvantage.