D Development in the transportation sector is being rapidly with the aim ofovercoming stagnation in Jakarta. Jakarta's Mass Rapid Transit (MRT), which is arail-based transportation mode, is one of the solutions to overcome this stagnation.MRT Jakarta is already operating in phase 1 of the Lebak Bulus – Bundaran HIroute and will continue with the construction of phase 2 for the Bundaran HI – Kotaroute as the planning is expected to select the expected capacity of the tractionsubstation. Traction substations are specific substations that function to supplyelectricity to the Jakarta MRT train through the overhead power network (LAA).To select the capacity of the traction substation, it takes the supply distance betweenthe substations as well as the output power and peak load of the Jakarta MRT trainand then it is necessary to know the resistance value of the LAA network. From thecalculation results, the expected power capacity of the traction substation at theMonas traction substation is 3282.578 kW and the Kota traction substation is2987.0911 kW. In addition, the resulting losses come from the overhead powerconductor (LAA) as much as 22.8706 W using a resistance value of 2.1541 x 10^(-5) /m using feeder wire H325sq.mm X 3, messenger wire AL -T-bar conductor2456sq.mm, and contact/trolley wire GT110sq.mm.