A connection establishing method between two electronic devices is disclosed, which includes following steps: activating a connection establishing program in a first electronic device; searching at least one specified electronic device; reading a storage unit, wherein the storage unit includes a database, and the database stores a plurality of corresponding connection modes between a plurality of second electronic devices and the first electronic device; pairing the searched specified electronic device with the database. If the second electronic devices include the specified electronic device, a connection between the specified electronic device and the first electronic device is established according to the corresponding connection mode. If the second electronic devices do not include the specified electronic device, a connection mode between the specified electronic device and the first electronic device is established and the database is updated.