Identification of external forces applied on a structure during its operational life is of practical importance for structural design and maintenance. Especially, identification using dynamic measurement has attracted much research interest because of its relative advantage in measurement. In this study, forces in 3 different types are identified experimentally, i.e. impact force, inertia force and sound pressure using Laser Doppler Vibrometer. Identification methods employed are: pseudo-inverse method and regularization method. Error obtained from each identification method and each experimental case is evaluated and the proposed method is shown to have wide applicability to various loading cases.