Electromechanical engineering of expressways is the key to the construction of smart expressways. The quality of materials and their standardized use directly affect the quality and service life of the project. The new materials are suitable for the mechanical and electrical construction scenarios and have prominent advantages. The key to their implementation lies in the quality control throughout the entire process. However, at present, there are shortcomings in promotion and quality control, such as lagging acceptance standards and mismatched processes. This article, based on the actual situation of mechanical and electrical construction and supervision in Guangdong, sorts out the current status of new material application and quality control, deeply explores the difficulties in control, and proposes optimization countermeasures in accordance with local standards, providing practical references for the high-quality construction of mechanical and electrical engineering on Guangdong's expressways.