Subject: the article proposes the methods for flexible regulation of administrative and organizational-technical relations between participants of the construction process which are based on integrated management contracts to address the issues related to realization of investment-construction projects in due time and within the funding limit under the influence of random factors. Research objectives: development of a conceptual simulation model of the process of making managerial decisions within the framework of realization of investment-construction project taking into account uncertainty. Materials and methods: We used the principles of the theory of control of technical and manufacturing systems, cybernetics, and also the methods of organizational, logical-semantic and simulation modeling, the works of domestic and foreign scholars on the problem under study. Results: by creating a functional simulation model for realization of investment-construction project, the construction process is considered as an iterative activity that is characterized by a list of indicators describing the state of the project at each control point. Controlled parameters include: planned indicators of the start and end date, and also the cost of execution of works depending on the project realization option (nomenclature of works, material and technical resources, labor intensity, machine capacity). Also, we characterize the basic criteria for efficiency of managerial influence on the realization of construction projects. Conclusions: we substantiated the necessity of taking into account the influence of random factors in the process of realization of investment-construction projects to determine more accurate predictive estimates of cost and duration of construction, especially for objects financed at the expense of state funds and built on the “fixed” contract price.