The rapid growth of Electronic Waste (E-waste) in recent years has created serious influences on the environment and society. The highly potential solution to mitigate this issue is the Reverse Supply Chain (RSC) which can reuse and recover E-waste materials. Risks generally derive from a RSC operation such as collection, transportation and treatment risks, but most studies ignore risk effects on the total cost of E-waste treatment in the RSC model. This paper aims to develop a mathematical model for an Ewaste RSC considering risk costs. This proposed model applied mixed integer linear programming and solved by a mathematical programming language. An illustrative example is examined to demonstrate the effectiveness of the proposed model. Sensitive analysis is also presented. The results can determine the optimal locations of facilities and the flow of materials or items in a RSC network. Furthermore, the network design decisions have been changed considerably while risk costs are incorporated.