The present disclosure provides a method and a device for arc fault detection for a photovoltaic inverter, and a photovoltaic inverter using the same. The method includes: acquiring current signals at a DC side of the photovoltaic inverter; obtaining frequency spectral characteristics of the current signal according to the current signal; judging whether the frequency spectral characteristics of the current signal have a frequency spectral characteristic of an arc; and if the frequency spectral characteristics of the current signal have a frequency spectral characteristic of an arc, shutting down the photovoltaic inverter, acquiring respectively a first input voltage when the photovoltaic inverter is shut down and a second input voltage after a predetermined time period after the shutdown, calculating a voltage drop from the first input voltage to the second input voltage, and judging whether an arc fault occurs according to the voltage drop.