Abstarct: The main and proposed topic of the present doctoral dissertation is the study of two important and very practical topics of location in the field of operations research and data envelopment analysis in the field of management and the combination of these two issues. Location is one of the most important and practical issues in the field of decision making that many criteria are effective in its analysis. Cost and system efficiency are also the most important criteria in the decision-making process. Considering these criteria simultaneously in the modeling of location problems helps decision makers to deal with the issue with more and more accurate information and provide results that are not obtained directly from other analytical tools. In this Thesis, we examine the combination of some location issues with the problem of data envelopment analysis and provide a solution and algorithm for it. The attitude we have towards combining these two issues is completely different from the combinations that have been proposed so far. We have also examined the inverse problem of locating a tree moderation from a more practical perspective, and we have examined some inverse problems of data envelopment analysis, which are very common in real life.