The invention discloses an industrial Ethernet device based on intrinsic safety and a signal processing method thereof. The device comprises a power module, as well as an Ethernet port, a signal conditioning module and an Ethernet communication module which are connected in sequence by signals; the power module is used for providing a power source needed by the device; the signal conditioning module is used for carrying out conditioning on the signal transmitted between the Ethernet port and the Ethernet communication module; the device also comprises a voltage limitation module; one end of the voltage limitation module is connected with the power module and the other end is respectively connected with the signal conditioning module and the Ethernet communication module; the voltage limitation module is used for carrying out voltage limitation protection on the power source and inputting the power source after voltage limitation protection into the signal conditioning module and the Ethernet communication module. The device carries out voltage limitation protection on the power source input into the device, thus leading the power source to be within a safe voltage range and improving the running safety of the device working in a danger area. The device can be safely applied to explosive danger occasions.