In a safety device for an elevator, on one car door among a pair of car doors, a light-emitting/light-receiving unit is disposed facing downward at an upper end position of a vertical line separated by a predetermined distance from an end face in a closing direction, which is to abut the other car door, toward the side of the other car door, and a first reflecting member is disposed facing upward at a lower end position of the vertical line. A housing space that houses the light-emitting/light-receiving unit in a state where both car doors are closed is formed on the other car door, and a second reflecting member is disposed facing upward at a bottom portion of the housing space and extends from the same position as an end face in a closing direction of the other car door toward the back of the housing space.