During the execution process of construction projects, supervision units often encounter sudden changes during the progress of construction. However, because general supervision man-hours are usually arranged in a flat manner, and it is normally without a response mechanism, it easily leads to final cost increases or surplus manpower. Using private projects as cases, this study adopts the concept of accumulated man-hours to establish a model that allows man-hours and construction progress to correspond with each other, so as to facilitate instant responses by the supervision units and manage the distribution of man-hour costs effectively. Finally, this research presents a Supervisory Strategy Model for Man-hours. This research is mainly divided into four parts. The first part defines the role of supervision according to laws, contracts, construction management systems and supervision unit organization. The second part divides types of supervision into four categories of continuous supervision, intermittent-inspection supervision, periodic supervision, and statutory-inspection supervision. The third part applies a case analysis to establish the corresponding relationship of the cumulative man-hours of supervision and the cumulative progress of a project, as well as to integrate the relationship between the man-hours and construction progress of the supervision business by merging the characteristics of the project timeline. The fourth part constructs a reasonable and safe strategy model that allows active control of the cumulative input ratio of man-hours, so as to facilitate the reasonable allocation and supervision of the total man-hours.