Abstract: A many-to-one transmission and information display method via local area network is implemented in a local area network comprising a first electronic device, at least one second electronic device, and at least one processing device connected to an output device to display information. In this method, a predetermined display information to be transmitted to the processing device is adjusted in advance based on a frame layout by the first electronic device and the second electronic device, respectively; then the adjusted predetermined display information is transmitted to the processing device to be integrated into the display information for the output device to display, thereby reducing the amount of data for transmission and the computation of integration process. A many-to-one transmission and information display system via local area network is also disclosed.