A new method for simple prediction of the impact force history on composite laminates subjected to low-velocity impact is proposed. First, the impact force history is calculated from the impact response analysis using the finite element method incorporated with the modified Hertzian contact law. Frequency characteristics of the numerical impact force history are investigated from modal analysis and compared with the natural frequencies of the system in which the mass of an impactor is lumped with the plate. The present method can be efficiently applied to isotropic or orthotropic plates with unknown contact laws as well as composite laminates with no restraint on the material properties and the geometrical shape. Predicted impact force histories using the present method are compared with the numerical ones from the impact response analysis using the contact law as well as the experimental result using a drop weight type impact test system.