The present invention discloses a method for obtaining IPv6 configuration information in an IPv6 transition network. The network includes an IPv4 network and an IPv6 network. An apparatus for providing IPv6 configuration information in the IPv4 network receives an IPv6 configuration information obtaining request packet sent by a user side device. In response, the apparatus sends a response packet to the user side device, where the response packet is a DHCPv4 packet, and carries the requested IPv6 configuration information. Some of the advantages of the present invention are that automatic configuration for a user side device which needs to traverse the IPv4 network to access the IPv6 network is implemented, and efficiency is greatly improved compared with a manual configuration method in the prior art.