The audit and supervision of government investment projects and major public works(hereinafter referred to as government investment projects)is the statutory duty of the audit department.Engineering cost is the most important cost expenditure in construction projects and has always been an important part of investment auditing.In the audit work of government investment projects,it is necessary to raise awareness of the importance of engineering cost audit of government investment projects and effectively supervise the implementation of engineering cost.The article starts with the importance of improving the supervision of engineering cost audit,and elaborates on the current application status,types and content,common methods,problem characterization,and result application of engineering cost audit supervision.It provides reference for audit departments and relevant units to engage in or participate in government investment project audit work,especially in the supervision of engineering cost implementation.