Abstract: Firstly, the definition and classification of failure modes and the classification of fracture were briefly introduced. Then, the distinguishing methods of all kinds of first-order failure modes and the analysis technique of fracture source were summarized. Finally, the application and importance of macro analysis technique in failure analysis were exemplified. The results show that in machanical equipment failure analysis, thorough and detailed macro analysis could help to narrow the analysis range, determine the analysis object and clear the analysis direction, and it plays a leading role in the whole process of failure analysis. The macro analysis technology has been widely used in the determination of the first-order failure modes and the determination of the main cracks or the fracture sources. Especially, it has an important role in deformation failure, corrosion failure and wear failure. Some failure reasons caused by defects could be found out only through macro analysis technique.