Pressure ulcer is a symptom frequently found in the patients incapable of moving for themselves in paraplegia or defects in central nervous system. It is caused mainly from chronic pressurization of skin tissue, but many other factors are also reported to promote the pressure ulcer. Shear force is among them. Biomechanical researches suggest mechanochemical reaction of cell that can disturb to repair the wound tissue, however, few studies were made about the relationship between the shear force and the pressure ulcer, because of the difficulty in measuring the shear force without affecting the skin condition itself. To measure the shear force without such interference, we have developed a planar shear force gauge, and measured the skin shear force for its preliminary evaluation. The device was found to be useful for the measurement of the local shear force and the skin deformation. However, further investigation on the material for the torsion frame and the fabrication accuracy is necessary.