Soil compaction involves a reduction in volume of the soil mass instead of settlement, which has been considered as one of the most important methods to increase geomaterials' strength in geotechnical engineering practice. This paper presents a numerical model to simulate soil compaction using the finite-element method with finite deformation. The fundamental formulations for soil compaction are introduced first. Then the model is employed to simulate the compaction process and predict spatial density, in which the soil is modeled as elastoplastic material. The Drucker–Prager/Cap model is integrated in the large-deformation finite-element code and used to model the gradual compaction process of soil. Representative simulations of practical applications in geotechnical/pavement engineering are provided to demonstrate the feasibility of predicting soil compaction density using the proposed large-deformation finite-element model.