We carried out detailed field surveys in the aftershock zone of the 2016 Kumamoto earthquake to ascertain whether surface fault ruptures appeared in association with this earthquake. As the result, we found fractures of the ground surface and destructions of artificial structures at many places in the eastern part of the Mashiki Town. These surface fractures found along two NE-SW and E-W trending lines in the area 1500m long and 500m wide. The surface fractures strike N65°±15E and have right-lateral strike displacements of 45-220cm The another surface fractures strike E-W and have left-lateral strike displacements of 10-30cm or more. These two fault systems were simultaneously formed in case of the Kumamoto earthquake. Furthermore, the fault is roughly E-W strike, characterized by many Riedel fractures that show shapes of mole tracks accompanying main sinistral displacements. Now, the teaching-materials development about the earthquake for junior high and high school students is recommended using the results of an investigation of the Kumamoto earthquake.