This article is a study of the artisanship involved in the construction of Iranian Watermills, and the cultural aspects of a traditional architecture that incorporates an understanding of constructions that date back centuries. Expanding the existing knowledge of these heritage properties and explaining their current condition in order to express the need for the preservation of ancient artisanship as part of a sustainable conservation future are the other prominent concerns of this work. Herein, historical and contemporary documents and travel accounts concerning the traditional buildings of the Iranian water-mills are studied to achieve a better understanding of the buildings background in the region. In addition, depending on the information accessibility and the existence of the constructions` remains, the authors chose some historical sites to be aware of the buildings` current condition and their exact functions based on observational studies. The article discusses that Iranian traditional Water mills represent knowledge of a highly developed technology which makes such ingenious use of natural resources without the consumption of additional power. Among different Iranian Traditional constructions, water-mills are the subject of the main body of this article.