Power system is a combination of large and complex electrical distribution networks. Protection is a critical issue in power system for both operational and safety reasons. An efficient protection scheme must have the capability to secure, that the power system works sufficiently, and ensures the equipment and additionally the general population from hazardous over voltages. The greatest challenge for electrical engineers is to provide better protection scheme to detect and locate the high impedance faults. The methods can be divided in to two categories, simple and artificial intelligent techniques. Simple technique include discrete wavelet transform and intelligent strategies incorporate artificial neural network, support vector machine, genetic algorithm, and fuzzy logic technique. All these techniques have their own merits and drawbacks. In this work, a large portion of the methods that have been discussed about since the past and usually used to detect and locate high impedance faults in appropriation system are reviewed.