Spark plug

The invention discloses a spark plug, and the spark plug comprises a spark plug body. The interior of the spark plug is provided with a central electrode, and one transition electrode or a plurality of transition electrodes in series connection are disposed below the central electrode. The transition electrode is fixed through a ceramic fixing support cooperating with the transition electrode. The bottom of the spark plug body is provided with a side electrode which can stabilize the ceramic fixing support. The spark plug is simple in manufacturing technology, is low in manufacturing cost, and is easy to implement. The transition electrode is firm in connection and is not liable to fall, and the insulation of the central electrode and the heat-dissipation performance of a piston cannot be affected. Moreover, the gap arrangement of the spark plug is scientific and reasonable. The spark plug improves the power of a generator, is low in consumption of fuel oil and gas, is low in gas emission, and is long in service life.