The purpose of this article is to explain the role of the laboratory in the quality control of seamless cylinders. First, in this article, the types, property, applications of compressed natural gas cylinders are discussed. Then the methods and processes of the production of these cylinders are reviewed. Afterwards, national and international standards, product approvals and tests that performed on gas cylinders are considered. Mechanical properties and Material tests, Destructive and Non-destructive tests are reviewed. At the result, can ensure reliability and desired quality of the CNG cylinders for the defined usage