A testing device includes a testing platform, a testing light source, a cover plate, a control circuit board, a probe and an adapter circuit board. The testing platform defines a receiving portion. The testing light source is positioned on the testing platform and opposite to the receiving portion. The cover plate is rotatably connected to the testing platform. The control circuit board is positioned on the testing platform. The probe and the adapter circuit board are positioned on the cover plate. The adapter circuit board is electrically connecting the probe to the control circuit board.