A vehicle-peripheral image displaying system comprising: a vehicle-mounted external camera mounted on a vehicle and configured to shoot an image of a vehicle-periphery; a monitor provided in a vehicle interior at a position to cause the monitor to be visible for a driver; and a monitor-image producing unit configured to produce an image to be displayed on the monitor based on an actually shot camera image input from the vehicle-mounted external camera, wherein: the monitor-image producing unit includes: an image processor configured to perform a viewpoint conversion of the actually shot camera image input from the vehicle-mounted external camera into a virtual camera image which is to be converted as if it is viewed from the driver's eye position; an image memory configured to store a vehicle interior image, being previously shot from the driver's eye position, as a vehicle interior image; and an image composition circuit configured to make the vehicle interior image output from the image memory translucent to form a translucent vehicle interior image, to perform an image composition such that the translucent vehicle interior image is superimposed on the virtual camera image output from the image processor, to produce a composite image representing the virtual camera image transparently through the translucent vehicle interior image, wherein the monitor-image producing unit outputs the composite image generated by the image composition circuit to the monitor such that the composite image is displayed on the monitor, the image composition circuit displays an area, in which the vehicle is vertically projected on a road surface, as a shadow in an entire area of the vehicle image being previously shot from the driver's eye position, the image composition circuit includes a blending circuit configured to set, of the vehicle interior image, the shadow area in which the vehicle is projected on the road surface as an opaque part having a transmissivity of 0 % of the vehicle interior image, and set an area corresponding to a window glass of the vehicle as a transparent part having a transmissivity of 100 % of the vehicle interior image, also set areas other than the shadow and the window glass as a translucent part having an arbitrary transmissivity. a vehicle-mounted external camera mounted on a vehicle and configured to shoot an image of a vehicle-periphery; a monitor provided in a vehicle interior at a position to cause the monitor to be visible for a driver; and a monitor-image producing unit configured to produce an image to be displayed on the monitor based on an actually shot camera image input from the vehicle-mounted external camera, wherein: the monitor-image producing unit includes: an image processor configured to perform a viewpoint conversion of the actually shot camera image input from the vehicle-mounted external camera into a virtual camera image which is to be converted as if it is viewed from the driver's eye position; an image memory configured to store a vehicle interior image, being previously shot from the driver's eye position, as a vehicle interior image; and an image composition circuit configured an image processor configured to perform a viewpoint conversion of the actually shot camera image input from the vehicle-mounted external camera into a virtual camera image which is to be converted as if it is viewed from the driver's eye position; an image memory configured to store a vehicle interior image, being previously shot from the driver's eye position, as a vehicle interior image; and an image composition circuit configured to make the vehicle interior image output from the image memory translucent to form a translucent vehicle interior image, to perform an image composition such that the translucent vehicle interior image is superimposed on the virtual camera image output from the image processor, to produce a composite image representing the virtual camera image transparently through the translucent vehicle interior image, wherein the monitor-image producing unit outputs the composite image generated by the image composition circuit to the monitor such that the composite image is displayed on the monitor, the image composition circuit displays an area, in which the vehicle is vertically projected on a road surface, as a shadow in an entire area of the vehicle image being previously shot from the driver's eye position, the image composition circuit includes a blending circuit configured to set, of the vehicle interior image, the shadow area in which the vehicle is projected on the road surface as an opaque part having a transmissivity of 0 % of the vehicle interior image, and set an area corresponding to a window glass of the vehicle as a transparent part having a transmissivity of 100 % of the vehicle interior image, also set areas other than the shadow and the window glass as a translucent part having an arbitrary transmissivity.