The form in frontal view of the recent human facial skeleton, including the frontal bone, was simulated under the condition of uniform strength to cope with the forces in the chewing action, by using the two-dimensional frame model made of members with step-wise variable cross-sections and by using the finite element analysis method. The simulation, in which the condition was applied to the elements of the model in the frontal bone region, resulted in a form different from the actual facial skeleton But the simulation in which the condition was not applied to the above elements resulted in a form tolerably similar to the actual facial skeleton. Hence, it was concluded that the biomechanical role of the frontal bone was different from that of the facial bones: the former was part of the brain casing and the latter a chewing machine, including the casings of the eyes and the nose, regulated by the law of uniform strength to cope with the forces in the chewing action.