In order to evaluate and track the construction risk of weaponry and equipment system of systems (WESoS) timely and exactly, a fuzzy integration evaluation of the construction risk factor of WESoS is given. Analysis of the sources and elements of construction risk of WESoS, the construction risk of WESoS was divided into five grades. The concept of risk factor was introduced and a risk evaluation model was given, after that, the five grades fuzzy integration evaluation of WESoS construction risk based on the model was discussed. The model is of impersonality and in reason, which provided a simple and practical method for construction risk evaluation of weaponry and equipment system of systems.