In order to test a semiconductor spark plug, a test method comprises a step consisting of depositing water on the head of the spark plug, between the two electrodes of same, so that the water forms a water meniscus covering the semiconductor element of the head, a step consisting of applying, between the first terminal and the second terminal of the spark plug, a voltage equal to the operating voltage of the spark plug, a step consisting of identifying at least a first characteristic of electric arcs induced between the electrodes during the application of the voltage, and a step consisting of determining the operational or defective character of the spark plug according to the first characteristic of the electric arcs. This test method is particularly reliable and does not require constraining provisions in order to ensure the safety of the operators implementing the method.