Abstract: In the cost control of highway engineering, it is necessary to optimize the project management from the perspective of the whole process to control the project cost reasonably. In order to ensure that the cost control of highway projects can achieve the expected effect and reduce the economic loss of facilities, it is necessary to conduct a comprehensive analysis of each stage of the construction of highway engineering projects, so as to achieve the cost control of the whole process. Based on this, this paper expounds the importance of cost control in highway engineering management and the basic principles of project cost management. The relevant problems of cost control are analyzed, and finally the relevant strategies for optimizing the cost control of the whole process of highway engineering are proposed. From the perspective of cost control, the application of the whole process cost control concept enables project management personnel to control every construction detail, so as to comprehensively prevent and control the risk of changes in construction costs and promote the healthy and long-term development of the project.