A power control method, comprising: determining, by a first terminal device, a transmit power of a data channel, wherein the transmit power of the data channel comprises a transmit power of a first data channel part and a transmit power of a second data channel part, the first data channel part and the second data channel part constitute the data channel, wherein the first data channel part is a part of the data channel that has a same time domain resource with a control channel and does not overlap the control channel in frequency domain, and the second data channel part is another part of the data channel that has a different time domain resource to the control channel and overlaps the control channel in frequency domain; wherein: P 2 = P 1 + 10 log 10 M / M − N dBm, wherein P 2 is the transmit power of the second data channel part, P 1 is the transmit power of the first data channel part, a bandwidth of the control channel is N, a bandwidth of the data channel is M, a bandwidth of the first data channel part is M-N, and a bandwidth of the second data channel part is M, wherein M is greater than N; and sending, by the first terminal device, data in the first data channel part to a second terminal device at the transmit power of the first data channel part, and sending data in the second data channel part to the second terminal device at the transmit power of the second data channel part. determining, by a first terminal device, a transmit power of a data channel, wherein the transmit power of the data channel comprises a transmit power of a first data channel part and a transmit power of a second data channel part, the first data channel part and the second data channel part constitute the data channel, wherein the first data channel part is a part of the data channel that has a same time domain resource with a control channel and does not overlap the control channel in frequency domain, and the second data channel part is another part of the data channel that has a different time domain resource to the control channel and overlaps the control channel in frequency domain; wherein: P 2 = P 1 + 10 log 10 M / M − N dBm, wherein P 2 is the transmit power of the second data channel part, P 1 is the transmit power of the first data channel part, a bandwidth of the control channel is N, a bandwidth of the data channel is M, a bandwidth of the first data channel part is M-N, and a bandwidth of the second data channel part is M, wherein M is greater than N; and wherein the first data channel part is a part of the data channel that has a same time domain resource with a control channel and does not overlap the control channel in frequency domain, and the second data channel part is another part of the data channel that has a different time domain resource to the control channel and overlaps the control channel in frequency domain; wherein: P 2 = P 1 + 10 log 10 M / M − N dBm, wherein P 2 is the transmit power of the second data channel part, P 1 is the transmit power of the first data channel part, a bandwidth of the control channel is N, a bandwidth of the data channel is M, a bandwidth of the first data channel part is M-N, and a bandwidth of the second data channel part is M, wherein M is greater than N; and sending, by the first terminal device, data in the first data channel part to a second terminal device at the transmit power of the first data channel part, and sending data in the second data channel part to the second terminal device at the transmit power of the second data channel part.