A connection setting method using a barcode pattern, a connection setting system and user equipment (UE) thereof are provided. The method includes the following steps. A connection application is installed in each of at least two pieces of UE respectively. First UE performs setting for connecting to an electronic device by a default mode and generates the barcode pattern accordingly. Then, an image capture unit of second UE is activated to capture the barcode pattern. The barcode pattern is analyzed by the connection application of the second UE, so as to obtain a plurality of parameters of connection setting in regard to the electronic device. Connection setting is performed automatically according to the parameters, such that the second UE connects to the electronic device and performs data transmission.