A device for realizing upstream aggregation and downstream translation of a virtual local area network (VLAN) includes a buffer and a processor. The buffer is used for storing an ingress VLAN translation table and an egress VLAN translation table. The processor is used for translating an upstream packet inputted from a first user port into an upstream translation packet according to the ingress VLAN translation table, and transmitting the upstream translation packet to the Internet through an internet port, and translating a first downstream packet inputted from the internet port into a first downstream translation packet according to the egress VLAN translation table, and transmitting the first downstream translation packet to a user device through a second user port.