The present invention discloses a system for testing illuminating elements and a method for testing illuminating elements, wherein the method includes the following steps. Firstly, an illuminating element and an unilluminated area on a circuit board are covered respectively. A reference voltage is obtained according to a brightness of the unilluminated area and a testing voltage is obtained according to a brightness of the illuminating element being driven. Afterwards, whether the illuminating element passes a testing process or not is judged from the reference voltage and the testing voltage.