A multi-chip connection circuit (10, 30), comprising: a system-on-a-chip (100, 400, 901), comprising: a digital baseband circuit (110, 410), configured to transceive and process digital data; and a first transmission interface (120, 420, 430), coupled to the digital baseband circuit (110, 410), and receiving or transmitting the digital data according to a high speed serial input/output standard; and a radio frequency chip (200, 500, 700, 902, 903, 904), comprising: a second transmission interface (220, 520, 720), coupled to the first transmission interface (120, 420, 430), and transceiving the digital data; and a radio frequency chain module (210, 510, 710), coupled to the second transmission interface (220, 520, 720), and converting the digital data into a sending analog signal, or converting a receiving analog signal into the digital data; wherein the system-on-a-chip (100, 400, 901) and the radio frequency chip (200, 500, 700, 902, 903, 904) are disposed on the same circuit substrate, and the first transmission interface (120, 420, 430) and the second transmission interface (220, 520, 720) are connected through a transmission conductor on the circuit substrate, wherein the second transmission interface (220, 520, 720) transmits the digital data to the digital baseband circuit (110, 410) or receives the digital data from the digital baseband circuit (110, 410) through the first transmission interface, and the radio frequency chain module (210, 510, 710) comprises: a digital-to-analog converter (211, 511, 711), converting the digital data into the sending analog signal; an analog-to-digital converter (212, 512, 712), sampling the receiving analog signal to generate the digital data; and a transceiver (213, 513, 713), coupled to the digital-to-analog converter (211, 511, 711) and the analog-to-digital converter (212, 512, 712), and performing filtering and power amplification to the sending analog signal or the receiving analog signal. a system-on-a-chip (100, 400, 901), comprising: a digital baseband circuit (110, 410), configured to transceive and process digital data; and a first transmission interface (120, 420, 430), coupled to the digital baseband circuit (110, 410), and receiving or transmitting the digital data according to a high speed serial input/output standard; and a digital baseband circuit (110, 410), configured to transceive and process digital data; and a first transmission interface (120, 420, 430), coupled to the digital baseband circuit (110, 410), and receiving or transmitting the digital data according to a high speed serial input/output standard; and a radio frequency chip (200, 500, 700, 902, 903, 904), comprising: a second transmission interface (220, 520, 720), coupled to the first transmission interface (120, 420, 430), and transceiving the digital data; and a radio frequency chain module (210, 510, 710), coupled to the second transmission interface (220, 520, 720), and converting the digital data into a sending analog signal, or converting a receiving analog signal into the digital data; a second transmission interface (220, 520, 720), coupled to the first transmission interface (120, 420, 430), and transceiving the digital data; and a radio frequency chain module (210, 510, 710), coupled to the second transmission interface (220, 520, 720), and converting the digital data into a sending analog signal, or converting a receiving analog signal into the digital data; wherein the system-on-a-chip (100, 400, 901) and the radio frequency chip (200, 500, 700, 902, 903, 904) are disposed on the same circuit substrate, and the first transmission interface (120, 420, 430) and the second transmission interface (220, 520, 720) are connected through a transmission conductor on the circuit substrate, wherein the second transmission interface (220, 520, 720) transmits the digital data to the digital baseband circuit (110, 410) or receives the digital data from the digital baseband circuit (110, 410) through the first transmission interface, and the radio frequency chain module (210, 510, 710) comprises: a digital-to-analog converter (211, 511, 711), converting the digital data into the sending analog signal; an analog-to-digital converter (212, 512, 712), sampling the receiving analog signal to generate the digital data; and a transceiver (213, 513, 713), coupled to the digital-to-analog converter (211, 511, 711) and the analog-to-digital converter (212, 512, 712), and performing filtering and power amplification to the sending analog signal or the receiving analog signal. a digital-to-analog converter (211, 511, 711), converting the digital data into the sending analog signal; an analog-to-digital converter (212, 512, 712), sampling the receiving analog signal to generate the digital data; and a transceiver (213, 513, 713), coupled to the digital-to-analog converter (211, 511, 711) and the analog-to-digital converter (212, 512, 712), and performing filtering and power amplification to the sending analog signal or the receiving analog signal.