A liquid-discharge-failure detecting apparatus includes a light-emitting element and a light-receiving element. The light-emitting element emits a laser beam in a direction that intersects with a direction in which a droplet of liquid is discharged. The beam is elliptical in cross section. The light-receiving element receives a scattered light generated by scattering of the laser beam by the droplet. The light-receiving element is externally adjacent to a circumference of the beam at a position where a beam diameter of the beam is small.