PROBLEM TO BE SOLVED: To provide an interconnection inverter device which enables the increase in the control accuracy of an AC-terminal output voltage, and the increase in amount of generated power.SOLUTION: An interconnection inverter device 2 operable to output AC power to a system 3 comprises: a voltage sensor 10 for measuring an output voltage of an inverter 5; a current sensor 13 for measuring AC output current of the inverter 5; a storage part 16 for storing the impedance of a wiring line between a measurement point where the voltage sensor 10 measures the output voltage, and an AC output terminal 9 of the interconnection inverter device 2; a voltage drop-calculating unit 14 for calculating an amount of voltage drop based on the impedance stored by the storage part 16, and AC output current measured by the current sensor 13; and a subtraction unit 15 of correcting the output voltage by subtracting the amount of voltage drop from an output voltage measured by the voltage sensor 10. When the output volta
