A method for supporting access of a Point to Point Protocol over Asynchronous Transfer Mode (PPPoA) terminal including: the PPPoA terminal initiates a Point to Point Protocol (PPP) negotiation to a broadband access device based on an Internet Protocol (IP) architecture; the broadband access device assigns a Media Access Control (MAC) address to the PPPoA terminal, builds a Point to Point Protocol over Ethernet (PPPoE) connection between itself and a Broadband Access Server (BAS) and acquires a Session ID; the broadband access device converts a PPPoA packet sent by the PPPoA terminal into a PPPoE packet and sends the PPPoE packet to the BAS according to the MAC address and Session ID, and converts the PPPoE packet sent by the BAS into the PPPoA packet and sends the PPPoA packet to the PPPoA terminal. A device for supporting the access of a PPPoA terminal is provided.