Risk as, an uncertain event, or condition that if it occurs, has a positive or negative effect on a project's objective. Risk analysis is done via interviews and brainstorming considering the available and extensive experience of the involved stakeholders. Each identified risk is prioritized through a qualitative risk analysis process considering the probability of occurrence and the impact by project stakeholders. The results of risk management planning processes are used to update/re-plan the project management plan to consider the risk effect on the project. The biodiesel project is very profitable, the economic indicators for the project are very high, and the execution of such a project will strengthen the national economy. Therefore, a biodiesel risk analysis is performed to achieve security for the plant. The depletion of fossil fuel forces the world to look for alternative ways for energy production. The most common way is the production of biodiesel from waste cooking oil. This paper presents a detailed cost analysis for a biodiesel plant with capacity 100,000 ton/year.