Electricity is delivered to end users through generation, transmission, and distribution phases. The most important issues during energy journey is to provide selective, rapid, and safe protection to ensure energy continuity. In this context, when the operating conditions defined in the protection systems are exceeded, an effective protection system and coordination are required to provide that as few consumers as possible are affected by the energy outage and reliably isolate the fault. If the short circuit is not separate from the network quickly after a short circuit occurs, network equipment and electrical devices may be damaged because of overcurrent that occurs. In this study, the coordination of overcurrent protection relay at 34.5 kV voltage level of the distribution network in Sakarya Province, Serdivan District, Yazlık region is made and MATLAB/Simulink is used in the modeling of the system. All data of inspected distribution network is embedded to MATLAB/Simulink file and then optimum protection is provided on relay coordination settings by performing power flow analysis and short circuit calculations.