A rolling-ball switch is adapted to be fixed on a circuit board, and includes a conductive housing defining a receiving space and having two opposite open ends, two conductive balls disposed movably in the receiving space, two insulation caps covering respectively the open ends to confine the conductive balls in the receiving space, and two terminals connected fixedly and respectively to the insulation caps. The receiving space has first and second widths along first and second directions that are perpendicular to each other. The first width is larger than the sum of diameters of the conductive balls, the second width is larger than the diameter of each conductive ball, and the diameter of each conductive ball is larger than a distance between an inner section of the respective terminal that extends into the receiving space and an inner wall of the conductive housing.