The category of economic uncertainty is the subject of research by a number of economic schools, the subject of long-term discussions, the need for which has not lost its importance in the context of modern geopolitical upheavals and digital transformations of modern economic systems. We consider it possible to include ideas that uncertainty is an immanent property of the functioning of complex self-developing systems among the provisions that are a consensus. The contribution investigates conceptual foundations of the uncertainty theory. The genesis of uncertainty is interpreted as an essential property of complex self-developing systems, which at points of high critical instability acquire the possibility of a variety of alternative development depending on a number of random non-deterministic phenomena and processes. The systemic and informational nature of uncertainty is analyzed. The issues of morphology of uncertainty are considered: its forms, types, levels, patterns of dynamics, interaction with related phenomena and processes such as risk, stability, safety, etc. It is concluded that technology is needed to transform uncertainty into a manageable and measurable risk.