Project cost settlement audit is an important link of project cost management, and its audit quality is directly related to the reasonable use of project costs. However, there are many problems in the actual work, such as formalism in the settlement work, the audit professional level needs to be improved, and the supervision mechanism is not perfect, which affects the quality of the audit work. In view of these problems, this paper puts forward corresponding countermeasures and suggestions: strengthening the review of the substantive content of settlement audit, improving the professional quality of settlement personnel, and improving the supervision mechanism of project cost settlement. These measures are helpful to standardize audit behavior, improve audit quality and project cost management level.