The failure of the projects and their complexity it has increased over the years. The main reasons of failure are uncertainty and RM. Uncertainty is a completely unknown outcome, with a lack of background information of an event. The research will be conducted through qualitative method, survey (questionnaires), from 94 respondents, to offer in-depth and thorough data study. Qualitative technique is used to explain the collected data in terms of the applied process. A Questionnaire will be used from Project Managers in the period of 2018. The ANOVA analysis will be applied in the research, five points Likert scaling as well as Standard Multiple Regression Analyses. The study analyses the obstacles and provides suggestions and recommendations in solving the difficulties that the management is facing with uncertainty and enterprise risk in complex projects in the Kingdom of Bahrain.

Keywords : Uncertainty, RM, Complex Projects.