With recent advancements and advent of industry 4.0 model, industries are transforming the traditional methods to intelligent and digitization techniques, which create high demand for scientific and effective health management of mechanical equipment. The aim of this paper is to do a comparative study of different fault diagnosis techniques in rolling elements bearing. It will also help to better understand the process and approaches of all types of fault detection techniques, which will give new insights for the research leading to further improvement in the performance of rolling elements bearing. Early and accurate identification of the fault is of paramount importance, as it can help to further prevent the wear and tear of the machine and to preserve the rolling machine work in a healthy atmospheric state.