Network system of home appliance and network setup method of the same

A home appliance comprises a communication circuitry, an input unit configured to receive an input for controlling the home appliance, and at least one processor configured to control the communication circuitry to operate in the first mode in response to detecting the button being pressed, establish a first communication interface with an external terminal, obtain, via the first communication interface, network set-up information including a Service Set Identifier (SSID) of an external wireless access point apparatus and authentication information to access the external wireless access point apparatus. The SSID is selected via the external terminal and the authentication information was previously stored in the external terminal, control the communication circuitry to operate in the second mode, establish a second communication interface with the external wireless access point apparatus using the obtained network set-up information, and control the communication circuitry to access an external server via the second communication interface.