Relations with the external environment are important for the survival of organizations. In the theoretical context, the new institutional theory deals with relations with the external environment in terms of “uncertainty”. Investigation of the effects of uncertainties is important for predicting reactive or proactive approaches of organizations in uncertain environments. This study aims to investigate the effect of uncertainties in the context of environmental adaptation and response within the framework of organizational uniformity. It discusses the types of organizational isomorphism and evaluates the concept of uncertainty with the new institutional theory perspective. In this scope, organizations implement an institutionalized structure in the process of adapting to the organizational environment, and this structure changes based on the relations with the organizational environment. In this change, the possible factors that will affect the approaches of the organizations include the interactions of the organizations with the actors in their external environment, social, economic, political elements, technological developments and the tendency to avoid uncertainty on the basis of the country and country groups in which they operate.