Spark plug with double electrical discharge comprising: - a central electrode connected to a pulse high voltage power supply having a discharge surface, said central electrode being placed concentrically on a longitudinal central axis (y) of the spark plug and extending along it; and - a ground electrode placed concentrically with the central electrode having a discharge surface oriented towards the discharge surface of the central electrode, - an insulator placed concentrically on the longitudinal central axis (y) of the spark plug, between the central electrode and ground electrode on whose exterior circumference, in a parallel plane with the discharge surface of the ground electrode, there is a groove accommodating an intermediate electrode provided with two superior (1.3) and inferior (1.4) opposing discharge surfaces, wherein - the superior surface (1.3) is oriented towards the discharge surface of the central electrode, and - the inferior surface (1.4) is oriented towards the discharge surface of the ground electrode, characterized in that: - the intermediate electrode has a shape of a flat washer with a central hole and protrusions arranged towards the exterior circumference of the washer allowing positioning of at least two superior mini electrodes on the intermediate electrode, on the superior discharge surface (1.3) of the intermediate electrode, and of at least two inferior mini electrodes on the inferior discharge surface (1.4) of the intermediate electrode, at a predetermined distance between said superior and inferior mini electrodes (5, 6); - on the discharge surface of the ground electrode there are at least two ground mini electrodes, placed at a predetermined distance from said superior and inferior mini electrodes (5, 6), and - the total number of superior, inferior and ground mini electrodes (5, 6, 7) is at least 6 and at most 54, and the number of inferior mini electrodes equals the number of ground mini electrodes, such that a simultaneous ignition of an electrical discharge generated between the central electrode and the intermediate electrode and of an electrical discharge generated between the intermediate electrode and the ground electrode upon initiation of combustion is generated. - a central electrode connected to a pulse high voltage power supply having a discharge surface, said central electrode being placed concentrically on a longitudinal central axis (y) of the spark plug and extending along it; and - a ground electrode placed concentrically with the central electrode having a discharge surface oriented towards the discharge surface of the central electrode, - an insulator placed concentrically on the longitudinal central axis (y) of the spark plug, between the central electrode and ground electrode on whose exterior circumference, in a parallel plane with the discharge surface of the ground electrode, there is a groove accommodating an intermediate electrode provided with two superior (1.3) and inferior (1.4) opposing discharge surfaces, wherein - the superior surface (1.3) is oriented towards the discharge surface of the central electrode, and - the inferior surface (1.4) is oriented towards the discharge surface of the ground electrode, characterized in that: - the intermediate electrode has a shape of a flat washer with a central hole and protrusions arranged towards the exterior circumference of the washer allowing positioning of at least two superior mini electrodes on the intermediate electrode, on the superior discharge surface (1.3) of the intermediate electrode, and of at least two inferior mini electrodes on the inferior discharge surface (1.4) of the intermediate electrode, at a predetermined distance between said superior and inferior mini electrodes (5, 6); - on the discharge surface of the ground electrode there are at least two ground mini electrodes, placed at a predetermined distance from said superior and inferior mini electrodes (5, 6), and - the total number of superior, inferior and ground mini electrodes (5, 6, 7) is at least 6 and at most 54, and the number of inferior mini electrodes equals the number of ground mini electrodes, such that a simultaneous ignition of an electrical discharge generated between the central electrode and the intermediate electrode and of an electrical discharge generated between the intermediate electrode and the ground electrode upon initiation of combustion is generated. - the superior surface (1.3) is oriented towards the discharge surface of the central electrode, and - the inferior surface (1.4) is oriented towards the discharge surface of the ground electrode, - the intermediate electrode has a shape of a flat washer with a central hole and protrusions arranged towards the exterior circumference of the washer allowing positioning of at least two superior mini electrodes on the intermediate electrode, on the superior discharge surface (1.3) of the intermediate electrode, and of at least two inferior mini electrodes on the inferior discharge surface (1.4) of the intermediate electrode, at a predetermined distance between said superior and inferior mini electrodes (5, 6); - on the discharge surface of the ground electrode there are at least two ground mini electrodes, placed at a predetermined distance from said superior and inferior mini electrodes (5, 6), and - the total number of superior, inferior and ground mini electrodes (5, 6, 7) is at least 6 and at most 54, and the number of inferior mini electrodes equals the number of ground mini electrodes,