A careful attention paid to the writing of similar contracts, which each year provides a large number of designs, can prevent many challenges. In this research, identifed and investigate the advantages and disadvantages of the BOT contract (Journal 469) in Iran's industries (case study of water and wastewater projects), to identify the weaknesses, ambiguities, contradictions of 469, in order to provide a clearer picture of dimensions of these relationships and to present the main challenges of its projects. It is seen that these critical success factors are introduced but unambiguous descriptions of all critical success factors are missing which is an essential need. Hence, to understand more, the benefits and challenges of the BOT projects are discussed. In the four section, examples of different cases in the Iranian industry are presented and in these projects there are contractual challenges arising from BOT contract implementation that will be addressed. As the same way one of the challenges is the main and sub-stakeholders and how they relate to them and their performance in the projects that will be discussed in detail. This research is a qualitative one. By first using library studies and the use of internal and external articles and interviewing experts and extracting and using lessons learned from the projects in question. Projects in the industry were carried out using the BOT method. The key challenges and advantages and disadvantages of each were extracted using the BOT methodology implemented using the 469 Program and Budget Organization Journal. This publication is of the second group type and its use is compulsory and mandatory, but the change is arbitrary. In the meantime, all the key factors that a project needed to succeed were collected. Also, all important and influential stakeholders of the projects in question, their problems and their timelines were provided. The purpose is to explore the major challenges of BOT projects and to explore the advantages and disadvantages of using these types of contracts in real examples, and ultimately to provide an appropriate solution to reduce these challenges in similar contracts and other types.