A vehicle-operation assist includes a circumferential-state imager for imaging a circumferential state of a vehicle with a camera and generating a circumferential-state image; a synthetic-image generator for generating a synthetic image by superimposing on the circumferential-state image, an assumed-movement pattern of the vehicle performing a predetermined series of driving operations; and a display for displaying the synthetic image. The circumferential-state imager has at least one camera and a camera parameter table for storing characteristics of the camera and generating the circumferential-state image on the basis of the camera characteristics.