A setting and modifying method of a user operating interface is used between a user device and a digital audio/video signal receiving and processing device through a network. The setting and modifying method includes the following steps. Firstly, the user device acquires a first user operating interface setting information from the digital audio/video signal receiving and processing device. Then, the contents of the first user operating interface setting information are modified to generate a second user operating interface setting information. Afterwards, the second user operating interface setting information is transmitted from the user device to the digital audio/video signal receiving and processing device through the network for setting the user operating interface.