Power transmission and distribution systems are exposed to overcurrent flow into their elements. Due to short circuit, excessive load, incorrect design and ground fault overcurrent will occur and elements for overcurrent protections are an overcurrent relay. The proposed thesis is planned to introduce a new relaying algorithm by using Artificial Intelligence (AI) method, fuzzy logic approach. A fuzzy logic approach overcurrent protection relay was developed using conventional protective relay characteristics. In Addis Center substation network overcurrent relays are connected in both high and low voltage side of substation line but those conventional digital relays have some drawbacks such as it doesn’t give a response when there is open circuit, the relay was expected to open the nearby breaker but sometimes it opens the feeder breaker instead and the responses are relatively slower. In order to overcome those problems fuzzy based overcurrent relay will add improved human safety, system reliability and determining and increase fault detection sensitivity. Modeling substation for fault analysis on DigSilent will be executed to determine the input parameter of FL based OC relay and performance of FL based OC protection relay will be simulated using single diagram of the substation analyzed and also the proposed OC relay protection algorithm will be tasted in MATLAB simulation software. The study result can give to this substation a boost of response time improved in overcurrent protection and system reliability. And it is expected that a convincing model of fuzzy logic based overcurrent relay can be achieved.