This paper describes the opportunity of implementing a model of a Mho type distance relay with a three zones by using MATLAB/SIMULINK package. SimPowerSystem toolbox was used for detailed modeling of distance relay, transmission line and fault simulation. The proposed model was verified under different tests, such as fault detection which includes single line to ground (SLG) fault, double line fault (LL), double line to ground fault (LLG) and three phase fault, all types of faults were applied at different locations to test this model. Also the Mho R- jX plain was created inside this model to show the trajectory of measured apparent impedance by the relay. The results show that the relay operates correctly under different locations for each fault type. The difficulties in understanding distance relay can be cleared by using MATLAB/SIMULINK software.