Ethernet passive optical network （EPON） is a new technology for optical fiber accessing network, which has characteristics of low cost, high bandwidth, little electromagnetic interference, strong scalability, strong compatibility and so on. The condition monitoring and video surveillance system in smart substation have a feature of large data, but low real-time requirements. The condition monitoring and video surveillance system in substation are constructed with using EPON can effectively solve the problem of exports’ bandwidth allocation without using switches, and also can save the network construction investment and life-cycle maintenance costs, which is effective new network scheme for the condition monitoring and video surveillance system in smart substation. This paper analyzed the feasibility of the application of EPON technology in monitoring and video surveillance system in smart substation, and designed the construction scheme of EPON network for 220 kV smart substation, which can provide a new scheme for the data transmission in monitoring and video surveillance system in smart substation.