Frequency Response Analysis (FRA) is one of the most effective tools for the condition monitoring and mechanical fault detection of power transformers. Accurate interpretation of FRA is critical while evaluating the condition of a transformer. The analysis of FRA responses is done by comparing the measured parameters with the reference measurements that could be previous measurements on the same or identical units. For the accurate interpretation of FRA results, it is important to follow the recommendations given in IEEE guide, IEC standards. This paper presents the basic guidelines for developing a benchmark for the Interpretation and test procedures of the transformer Frequency Response Analysis based upon the analysis of standards, reports, guides and case studies published by IEEE, IEC and CIGRÉ etc.