A power semiconductor module configured to be applied to an electric-power conversion apparatus that converts an input direct-current voltage or alternate-current voltage into a predetermined alternate-current voltage and outputs the converted alternate-current voltage, the power semiconductor module comprising: a first pair of elements that includes a diode element and a MOS switching element connected in inverse parallel and is configured to operate as a positive side arm of the electric-power conversion apparatus; and a second pair of elements that includes a diode element and a MOS switching element connected in inverse parallel and is configured to operate as a negative side arm of the electric-power conversion apparatus, wherein the first and second pairs of elements are accommodated in one module to compose a 2-in-1 module, and the power semiconductor module further comprises external electrode terminals that enable series connection of the first and second pairs of elements; a resistor (RG1, RG2) being connected between a gate terminal and a source terminal of a MOS switching element composing each of the pair of elements (Q1, Q2); characterized in that a series circuit of an overvoltage clamping element (DZ1, DZ2) that clamps a gate-drain voltage of the MOS switching element to be equal to or lower than a withstand voltage of the MOS switching element ([Para. 0049] and a unidirectional conducting element (DX1, DX2) forward connected in a direction from a drain terminal (D1, D2) to the gate terminal (G1, G2) being connected between the gate terminal (G1, G2) and the drain terminal (D1, D2) of the MOS switching elements; a first voltage fixing element that fixes a gate potential of the MOS switching element of the second pair of elements to a potential of a direct-current power source of the MOS switching element (Para.) being connected to a gate terminal of the MOS switching element of the second pair of elements; and a second voltage fixing element that fixes a drain potential of the MOS switching element to the potential of the direct-current power source (Para., Figure 13) being connected between the gate terminal and a drain terminal of the MOS switching element of the second pair of elements. a first pair of elements that includes a diode element and a MOS switching element connected in inverse parallel and is configured to operate as a positive side arm of the electric-power conversion apparatus; and a second pair of elements that includes a diode element and a MOS switching element connected in inverse parallel and is configured to operate as a negative side arm of the electric-power conversion apparatus, wherein the first and second pairs of elements are accommodated in one module to compose a 2-in-1 module, and the power semiconductor module further comprises external electrode terminals that enable series connection of the first and second pairs of elements; a resistor (RG1, RG2) being connected between a gate terminal and a source terminal of a MOS switching element composing each of the pair of elements (Q1, Q2); characterized in that a series circuit of an overvoltage clamping element (DZ1, DZ2) that clamps a gate-drain voltage of the MOS switching element to be equal to or lower than a withstand voltage of the MOS switching element ([Para. 0049] and a unidirectional conducting element (DX1, DX2) forward connected in a direction from a drain terminal (D1, D2) to the gate terminal (G1, G2) being connected between the gate terminal (G1, G2) and the drain terminal (D1, D2) of the MOS switching elements; a first voltage fixing element that fixes a gate potential of the MOS switching element of the second pair of elements to a potential of a direct-current power source of the MOS switching element (Para.) being connected to a gate terminal of the MOS switching element of the second pair of elements; and a second voltage fixing element that fixes a drain potential of the MOS switching element to the potential of the direct-current power source (Para., Figure 13) being connected between the gate terminal and a drain terminal of the MOS switching element of the second pair of elements.