A review analysis of the most widely used methods of metal science expertise in terms of the overall complex of works of state or independent experts in assessing the quality of materials, in investigating the circumstances of work-related or criminal accidents has been carried out. The purposes of metal science expertise as a section of materials science and its role in solving the issues related to extraordinary situations have been shown. The objects of the considered type of expertise are given. The main methods in expert practice are mechanical, physical, chemical, and physicochemical methods designed to analyze properties, morphology, composition [elemental, molecular, phase (both qualitative and quantitative)], structure, properties of substances and materials. The most common questions of the expertise of metals and alloys have been reviewed. They relate to the study of the nature and circumstances of damage to objects, as well as the analysis of the materials from which they were made up: structures, tools made of metals and alloys, jewelries. In forensics, an art criticism expertise, an expertise of cold arms, technics, equipment, etc. can be carried out simultaneously. The characteristics of classification, identification and diagnostic methods have been systematized and tabulated in a table according to the types, control methods and their purpose. Destructive and non-destructive types of control have been briefly listed. The conditions of performing metal science expertise, the requirements on the equipment and the executors, the dependence of the control methods on the situation under consideration, on standards and technical regulations, as well as the capabilities of expert organizations hare been described. The results of the work are recommended to be used for the development of the training courses «Material Expertise», «Materials and Expertise of Transport Breakdowns», as well as in the presentation of the course «Mechanical Properties of Materials and Structural Integrity»