The invention applies to the technical field of optical communication and provides a substation optical communication design method and device. The method comprises the steps of receiving inter-station parameters, wherein the inter-station parameters comprise inter-station optical cable distance, the number of inter-station connectors and average loss of optical fiber fusion joints; determining optical interface types according to the inter-station optical distance, wherein one optical interface type corresponds to one piece of inter-station optical cable distance in a preset range; calculating an attenuation limited regeneration section length, a dispersion limited regeneration section length and transmission quality according to the inter-station parameters; and outputting an optical attenuation value or an optical amplification value needing to be added according to calculation results. According to the method, the problems that the calculation quantity is high and an error is liable to occur in an optical interface selection calculation process can be effectively solved; functions such as automatically calculating the regeneration section length and automatically generating transmission quality index estimation tables required in a communication design report can be realized; the working efficiency of communication designers of a substation is improved; and the method and the device are widely applied to the optical communication design of the substation.