Steam condensation is a common physical phenomenon in nature and plays an important role in various industrial processes. Therefore, the regulation mechanism of steam condensation process has been widely concerned by scholars in recent years. In this paper, the molecular dynamics simulation method is used to study the vapor condensation behavior of copper surface by constructing a secondary microstructure model. The influence of different geometrical characteristics on the condensation process was discussed by analyzing the nucleation and merging time of droplets, the vapor condensation snapshot, the total number of condensed water molecules and the total number of water molecules in the maximum condensed drop. With the increase of column width or column height ratio, the molecular weight of the total condensed water increases first and then decreases.