This study includes a search for economic features through Ibn Mamatis Laws of Diwans book, which is a topic that calls for shedding light on it and knowing its dimensions and aspects and its real impact on the reality of life in that era of Islamic civilizational history. The economic aspect has a direct impact on the relationship between society and the state. The main idea of dealing with this kind of studies is to shed light on an important figure who has an official status in the state and society, and the book he wrote has great scientific value and is considered an authentic historical document because it is an eyewitness to his era, and he has knowledge and erudition that talks about accurate information that he saw, lived and dealt with. During his tenure in high positions in the state, it is therefore important to stand on such type of studies, verify them, and know their details. In this study, we talk about the time period in which Ibn Mamati lived and wrote topics related to the economic aspect of Egypt in the Ayyubid era, as he was one of the prominent ministers in the Ayyubid state. We note that previous studies have focused on the political and military aspects, neglecting the economic, social and civilizational aspects and have not sufficiently shed light on these important and main aspects of peoples' lives. The strange thing is that most literary history books have neglected to mention the life of Ibn Mamati, so that the largest historical encyclopedia did not contain anything about the life of Ibn Mamati, except for some historians who referred to some information about his life and his book Laws of Diwans.