The issues of routing in the IMT-2020 / 5G transport network, as well as the hardware and software complex of equipment for the Backhaul segment and requirements for it are considered. Taking into account the need to form end-to-end connections in the 5G network, a method is proposed for constructing the optimal route at the optical level with a two-parameter metric and weighting coefficients for each parameter, which can be determined by the 5G scenario. The most important characteristics of the IMT-2020 / 5G network are recommended as criteria: delay and optical signal-to-noise ratio (OSNR).