A power converting apparatus for converting alternating-current power supplied from an alternating-current power supply into direct-current power, the power converting apparatus comprising: a first wire and a second wire each configured to be connected to the alternating-current power supply; a first reactor disposed on the first wire; a first arm including a first switching element, a second switching element, and a third wire including a first connection point, the first switching element and the second switching element being connected in series by the third wire, the first connection point being connected to the first reactor by the first wire; a second arm connected in parallel with the first arm, the second arm including a third switching element, a fourth switching element, and a fourth wire including a second connection point, the third switching element and the fourth switching element being connected in series by the fourth wire, the second connection point being connected to the alternating-current power supply by the second wire; a capacitor connected in parallel with the first and second arms, characterized by a current detecting unit for detecting a power supply current (Is) output from the alternating-current power supply, and the loss characteristics per switching event of the first switching element and the second switching element are configured to be better than loss characteristics per switching event of the third switching element and the fourth switching element, when a polarity of a power supply voltage (Vs) from the alternating-current power supply is positive, the third switching element is configured to be turned off and the fourth switching element is configured to be turned on, and when the polarity of the power supply voltage (Vs) is negative, the third switching element is configured to be turned on and the fourth switching element is configured to be turned off, and when the absolute value of the power supply current (Is) is equal to or less than a current threshold (β), the third switching element and the fourth switching element are not permitted to be turned on regardless of the polarity of the power supply voltage (Vs) to prevent a capacitor short circuit through the alternating-current power supply and the reactor, and when the power supply current (Is) is larger than the current threshold (β), the third switching element and the fourth switching element are permitted to be turned on, ON and OFF states of the third switching and the fourth switching element being controlled in accordance with the polarity of the power supply voltage (Vs). a first wire and a second wire each configured to be connected to the alternating-current power supply; a first reactor disposed on the first wire; a first arm including a first switching element, a second switching element, and a third wire including a first connection point, the first switching element and the second switching element being connected in series by the third wire, the first connection point being connected to the first reactor by the first wire; a second arm connected in parallel with the first arm, the second arm including a third switching element, a fourth switching element, and a fourth wire including a second connection point, the third switching element and the fourth switching element being connected in series by the fourth wire, the second connection point being connected to the alternating-current power supply by the second wire; a capacitor connected in parallel with the first and second arms, characterized by a current detecting unit for detecting a power supply current (Is) output from the alternating-current power supply, and the loss characteristics per switching event of the first switching element and the second switching element are configured to be better than loss characteristics per switching event of the third switching element and the fourth switching element, when a polarity of a power supply voltage (Vs) from the alternating-current power supply is positive, the third switching element is configured to be turned off and the fourth switching element is configured to be turned on, and when the polarity of the power supply voltage (Vs) is negative, the third switching element is configured to be turned on and the fourth switching element is configured to be turned off, and when the absolute value of the power supply current (Is) is equal to or less than a current threshold (β), the third switching element and the fourth switching element are not permitted to be turned on regardless of the polarity of the power supply voltage (Vs) to prevent a capacitor short circuit through the alternating-current power supply and the reactor, and when the power supply current (Is) is larger than the current threshold (β), the third switching element and the fourth switching element are permitted to be turned on, ON and OFF states of the third switching and the fourth switching element being controlled in accordance with the polarity of the power supply voltage (Vs).