預防性救濟乃指他人（含行政機關、公法人、私法人）違法之行為（或處分）而肇致有侵害訴訟當事人權利或利益之虞，此際利益關係人為防範或阻止前項違法（侵權）行為的發生，得於事前向法院提起訴訟，請求禁止或停止執行前項爭議行為。前項權利救濟方式乃屬事前的權利救濟，其與一般採取事後請求損害賠償的救濟方式，有顯著的不同。本文係以研究日本憲法訴訟有關預防不作為，而提起司法的事前救濟案例為中心，通常此種類型的訴訟事件，又以確認公法義務為前提。然而確認公法義務存在與否的訴訟案件，泰半以上渉及法令的違憲審査問題，甚至抽象的規範審査問題。本文雖然以研究日本的訴訟判例為重心，但論文中多數的訴訟判例或權利救濟事件係渉及公害、噪音、環境訴訟等現代型憲法訴訟問題，而諸如此類的憲法訴訟或救濟問題，相信不久的將來，我國亦會遭遇相同的處境。若就前瞻性的研究觀點而言，隣國日本的司法裁判經驗，確實値得提供我國作為爾後之參考與借鑑。

Prevent the succor be pointing the others (contain an administration organization, public laws person, private legal person) illegal behavior (or punishment) and with the result that has a worry of violating the right or benefit of the litigation the party concerned. At this time the benefit relation is artificial to guard against or keep the clause above from breaking the law (infringement) behavior of taking place. Get to initiate public prosecution toward the court in the before the event. The request forbids or stops carrying out the clause above a controversy behavior. The succor method of the clause above right is the right succor which belongs to before the event. It with adopt the succor method of the indemnity of the after the event request generally, which has a notable dissimilarity. This text is studying with a Japanese relevant prevention of the constitution litigation having no conduct, and brings up a judicial before the event succor a case for the center. Usually the litigation affairs take confirming a public laws obligation as a premise again.