To inexpensively provide a vehicle outside monitoring system for monitoring working conditions of a working machine mounted in a working vehicle and displaying it inside the vehicle, and to enable display eliminating a sense of incongruity due to display of moving images in a monitor in a direction different from the travelling direction of a machine body.

An image pick-up device (C) consisting of a digital camera (11), an image processing device (D), and the monitor (10) are set in the machine body (1). The digital camera (11) and the image processing device (D) are USB-connected, and the moving images picked up by the digital camera (11) are displayed in the monitor (10) through the image processing device (D). Furthermore, the image data picked up by the digital camera (11) are subjected to right-left inversion processing or rotation processing by the image processing device (D), and displayed in the monitor (10).