Power Systems are prone to damage due to overcurrent as a result of faults like ground faults, line faults, short circuit etc. In order to curb the damage caused by these faults suitable protects systems must be placed. The protection system usually consists of a primary system and a backup system with proper coordination between the two systems (i.e. their tripping time) in order to ensure proper clearance of faults in minimum time. In this paper, the optimization of overcurrent relays which are primarily used as backup systems against these faults are analyzed. The application of swarm intelligence algorithms: Ant Colony Optimization and Firefly Algorithm in radial system are done in order to obtain the time multiplier settings of the relays. This enables us to achieve proper coordination between the overcurrent relays in the network. © 2017 IEEE.