Traditional construction road alignment depends on manual experience, making it difficult to determine the optimal route in complex circumstances. This paper intends to utilize digital elevation models (DEM) for the automatic alignment of construction roads, reducing manual intervention and enhancing the efficiency of route selection. Based on the DEM model in the form of regular grids, this paper combines the A* search algorithm and multiple control points guidance to construct an intelligent alignment algorithm for construction roads. This alignment algorithm uses three-dimensional distance and slope as the assessment indicators to design the evaluation function, constrains the maximum slope of the generated path to satisfy the highway design specifications, and incorporates multiple control points guidance to decrease the search depth of the algorithm, achieving the automatic alignment of construction roads. This paper conducts a case study in the area where a certain project in Guangxi is located. The results indicate that the selected route by the improved A* algorithm meets the alignment requirements, and the selection method of the expansion coefficient k in this algorithm is summarized. This intelligent alignment method for construction roads provides a new solution for the alignment of construction roads and is conducive to improving the efficiency of construction road alignment.