Islamic views concerning international law in spite of being reflected in practical life of the prophet and its historical background as recorded in certain books unfortunately have not been treated in main fiqhi books befittingly. What made this issue necessary more than anything pertains to the important fiqhi effects of the titles of dar al-Islam and dar al-kufr. It is clear that these effects will be subject matter if such concepts become clear. So the author of this article tries to work out a rule or law in order to recognize dar al-Islam and dar al-kufr and their distinction from the point of views of jurisprudents.