Ethernet communication apparatus and bridge thereof

The utility model relates to an Ethernet communication device and a bridge thereof. The Ethernet communication device can obtain a required positive 5V DC voltage from a USB port of a computer device without requiring a DC power supply transformer which aims at the bridge in the mode of inbuilt or externally connected arrangement, wherein, the bridge is connected with an Ethernet network RJ45 port of the computer device and a power supply end of the USB port by a connecting device, and thus the communication device of the utility model can not only obtain power from the USB port of the computer device but also can perform the functions of modulation and transmission of Ethernet signals. The utility model has the advantages that the utility model can automatically obtain the required DC voltage for work from the computer device without the transformer which is inbuilt or externally connected; a driving program is not needed to be arranged in the computer device; besides, the utility model has the advantages of low cost and small volume.