A switching control device comprising: a drive circuit (21, 21A, 21B, 21C) including a first drive circuit switch and a second drive circuit switch, the first drive circuit switch having a first terminal that is connected to a control terminal of a switching element (Q1, Q2) connected to a DC power supply to be transformed and controlled to be turned on or off, and applies a voltage to the control terminal to turn on the switching element (Q1, Q2), the switching element (Q1, Q2) including an input terminal to which a current is input, an output terminal that outputs the current input from the input terminal, and the control terminal that controls the current flowing from the input terminal to the output terminal, the second drive circuit switch having a first terminal connected to a power supply for applying a voltage to the drive circuit (21, 21A, 21B, 21C) and a second terminal connected to said first terminal of said first drive circuit switch; and a reverse bias circuit (22, 22A, 22B) that includes a capacitor connected to the output terminal, and a coil having one end connected between the first terminal of the first drive circuit switch and the control terminal and the other end connected between the capacitor and the output terminal, wherein the other end of the capacitor being connected to a second terminal of said first drive circuit switch, wherein the coil has an inductance value capable of continuously outputting a reverse bias voltage to the output terminal by the reverse bias circuit (22, 22A, 22B) when the switching element (Q1, Q2) is turned off, and when an inductance value of the coil is L, a voltage applied to the drive circuit (21, 21A, 21B, 21C) is VCC2, an ON period per cycle during which the voltage is applied to the control terminal by the drive circuit (21, 21A, 21B, 21C) is Ton, an OFF period per cycle during which the voltage is not applied to the control terminal by the drive circuit (21, 21A, 21B, 21C) is Toff, and a current value of the control terminal applied by the drive circuit (21, 21A, 21B, 21C) is IG, the following equation is satisfied: L > VCC 2 × Ton × Toff / 2 × IG × Ton + Toff a drive circuit (21, 21A, 21B, 21C) including a first drive circuit switch and a second drive circuit switch, the first drive circuit switch having a first terminal that is connected to a control terminal of a switching element (Q1, Q2) connected to a DC power supply to be transformed and controlled to be turned on or off, and applies a voltage to the control terminal to turn on the switching element (Q1, Q2), the switching element (Q1, Q2) including an input terminal to which a current is input, an output terminal that outputs the current input from the input terminal, and the control terminal that controls the current flowing from the input terminal to the output terminal, the second drive circuit switch having a first terminal connected to a power supply for applying a voltage to the drive circuit (21, 21A, 21B, 21C) and a second terminal connected to said first terminal of said first drive circuit switch; and a reverse bias circuit (22, 22A, 22B) that includes a capacitor connected to the output terminal, and a coil having one end connected between the first terminal of the first drive circuit switch and the control terminal and the other end connected between the capacitor and the output terminal, wherein the other end of the capacitor being connected to a second terminal of said first drive circuit switch, wherein the coil has an inductance value capable of continuously outputting a reverse bias voltage to the output terminal by the reverse bias circuit (22, 22A, 22B) when the switching element (Q1, Q2) is turned off, and when an inductance value of the coil is L, a voltage applied to the drive circuit (21, 21A, 21B, 21C) is VCC2, an ON period per cycle during which the voltage is applied to the control terminal by the drive circuit (21, 21A, 21B, 21C) is Ton, an OFF period per cycle during which the voltage is not applied to the control terminal by the drive circuit (21, 21A, 21B, 21C) is Toff, and a current value of the control terminal applied by the drive circuit (21, 21A, 21B, 21C) is IG, the following equation is satisfied: L > VCC 2 × Ton × Toff / 2 × IG × Ton + Toff