The reliability of acquisition terminal is crucial for the safe operation of electricity information acquisition system. In this paper, the reliability evaluation model of the electricity information collection system is established, including the outage model of the acquisition terminal, the multi-dimensional feature factor association failure determination model and the risk assessment method. Sequential Monte Carlo method and non-sequential Monte Carlo method are used to evaluate the risk of the instance, and experimental results demonstrate that sequential Monte Carlo method is more suitable for the risk assessment of electricity acquisition system, since it adopts time sampling technology and can simulate the acquisition system on the time axis. Furthermore, multi-dimensional feature factor correlation model is adopted to judge whether the electricity information acquisition system is invalid and the relationship between the risk index of the electricity information acquisition system and the threshold value in the multi-dimensional characteristic factor correlation model is studied. Then the relationship curve between the risk index and the threshold value is obtained. It can be concluded from the instance that the optimal value of the threshold value is the inflection point in the curve.