Abstract: The present invention relates to a computer Ethernet card used for a passive optical fiber access network and its data transmission terminals. A hardware network system that is based on a PON system optical network unit and is coupled to a computer via PCI interfaces is disposed. The hardware network system includes an optical network unit and its peripheral circuits, an end of which is coupled to an access optical fiber via an optical fiber transceiver, and the other end of which is coupled to computer PCI interfaces via a giga-Ethernet MAC controller. The present invention provides a network card based on passive optical network, which utilizes the technology of passive optical network when accessing to an upper layer server, lengthens the access distance, and reduces the structure complexity and cost of FTTD.