[Problem] To provide a vehicle rearview mirror system which is capable of eliminating a circumstance that a driver feel a sense that something is wrong, even in a case where a screen of a display device is caused to one-to-one correspond with an aspect ratio of the vehicle rearview mirror, and the ratio of the display screen of the display device is made different from an aspect ratio of an image which is acquired by a vehicle-mounted camera. [Means for Solving the Problem] A vehicle rearview mirror system of the present invention has: a display device 9 to construct an image by an image signal having been output from an image receiving unit 2a of a vehicle-mounted camera 2 and then cause a display screen 9a to display the constructed image; and a vehicle mirror main body 3 in which the display device 9 is incorporated. A ratio between a width in a transverse direction and a width in a longitudinal direction of the screen 9a of the display device 9 is caused to one-to-one correspond to a ratio between a width in a transverse direction and a width in a longitudinal direction of the vehicle mirror main body 3. The display device 9 has a signal processing unit 11 which processes an image signal and then causes the display screen 9a to display a resultant image. Partway of a signal line SL between the image receiving unit 2a and the signal processing unit 11, there is provided an image signal clipping unit 17 to clip an image signal corresponding to an image portion which is unrequired for driving by the driver 4 from an image constructed by the image signal having been output from the image receiving unit 2a and then output the remaining image signals to the signal processing unit 11. The signal processing unit 11 constructs an image G1' of a ratio one-to-one corresponding to a ratio of the display screen 9a by a remaining image signal having been input.