Typically, inertial loads associated with flapping wing micro air vehicles are ignored for analysis and control law development purposes. The goal of this work is to compute the inertial loads associated with flapping a wing and compare those loads to aerodynamic loads. It is assumed that the wing is a rigid flat plate so that there is no in-plane, out-of-plane, or torsional bending of the wing. The analysis begins by computing the acceleration of the wing center-of-gravity over a complete wingbeat cycle. Newton’s second law is then used to compute the inertial forces and eventually, the inertial moments. Simulation results are provided which compare the magnitude of the inertial loads to the aerodynamic loads for a wing of varying geometry.