The default risk in electric Interruptible Load Management (ILM) can produce huge economic losses to the electric grid company. It is vital to evaluate the customers' default risk before signing up the ILM contracts for the electric grid company's healthy operation. This paper constructs an ILM default risk indexes evaluation system, and uses the Fuzzy Extend Analytic Hierarchy Process (FEAHP) which is an improvement of Analytic Hierarchy Process (AHP) to calculate the weights vectors of the indexes due to its advantages of solving the experts' vagueness in marking the pairwise comparing importance. The Fuzzy Evaluation Method and probability theory are selected to calculate the integrated possible risk values. Finally, the given example proves the feasibility of the models mentioned.