A signal transmission method is applied to a terminal, and includes: acquiring a first PUCCH signal and a second PUCCH signal, wherein the transmission duration of the first PUCCH signal is one designated symbol, and the transmission duration of the second PUCCH signal is greater than one designated symbol; replacing the DMRS of at S least one designated symbol in the second PUCCH signal with the first PUCCH signal to obtain a third PUCCH signal; and transmitting the third PUCCH signal to a base station, so that the base station recovers the first PUCCH signal from the third PUCCH signal, and demodulates the second PUCCH signal by taking the first PUCCH signal as the DMRS of the second PUCCH signal so as to obtain UCI carried by the second PUCCH signal.