Abstract: A wide-angle side mirror device with a mirror box having a front and a rear, and first and second side walls. An object window is disposed in the first side wall of the mirror box. An observation window is disposed in the second wall of the mirror box. An object mirror having a curved shape which is concave in horizontal cross section and convex in vertical cross section is disposed to face out the object window and diagonally rearwards. An observation mirror is disposed in the mirror box to reflect a mirror image from the object mirror through the observation window. The object mirror preferably has a doughnut or drum shape, and more preferably has a degree of curvature in horizontal cross section approximately the same as a degree of curvature in vertical cross section. The observation mirror is preferably a flat mirror. The device has a wide field of view and allows the driver of a vehicle to view road conditions at acute angle intersections from the driver's seat.