Optimized planning of an enterprise’s activity taking into account the risk and uncertainty of external and internal environment is a difficult methodological problem. Solving it is important for practical planning. Therefore, there is no doubt in the significance of the research subject. The purpose of the study is describing the entire process of enterprise management from new product development to its implementation in the conditions of risk and uncertainty in the external and internal environment. Planning is based on using a multilevel system of models. On the upper level, the key strategic indicators are achieved through developing and implementing innovations, mostly related to planning the manufacturing of new high-tech products. However, the effect of risks and uncertainty on the processes of development, production and sales of new products is the greatest at this level. The literature suggests to use stochastic graphs with returns for this purpose. This idea is also supported in this study. However, implementing this idea requires further methodological development and quantitative calculations. Coordinating strategic decisions and tactical plans is based on eliminating economic and other risks associated with the economic activities of the enterprise in tactical planning by generating stochastic reserves through implementing additional innovations, providing extra sales, profits and other indicators of the strategic plan. The organization of operational management of complex production is represented by an iterative, sliding process (reducing risks in production), which is realized taking into account the limitations of tactical control. Planning in similar industries is usually organized based on network planning, determining the critical path. However, the main problem is not solved, i.e., the limitations on using resources are not taken into account. An effective algorithm has not been developed to date for solving the problem arising in case such limitations are imposed. In this paper, we propose to solve such a problem with the help of models of network and operational-calendar planning, their system integration. It is also important that the problem of specifying work durations (operations) is not solved in integers.