A communication method, comprising: receiving, by a terminal device, first downlink control information from a network device, wherein the first downlink control information comprises a first hybrid automatic repeat request HARQ process number; receiving, by the terminal device on a first frequency band, a first data packet carrying a first transport block, and receiving, on a second frequency band, a second data packet carrying a second transport block, wherein the first HARQ process number corresponds to the first transport block on the first frequency band and the second transport block on the second frequency band, and the first transport block is the same as the second transport block; and performing, by the terminal device, joint decoding on the first data packet and the second data packet, wherein the first downlink control information comprises scheduling information of the first data packet and the second data packet; the first frequency band and the second frequency band belong to a first frequency band set, and the first frequency band set comprises at least two frequency bands; the receiving, by the terminal device, first downlink control information from a network device comprises: receiving, by the terminal device on the second frequency band, the first downlink control information from the network device; and before the performing, by the terminal device, joint decoding on the first data packet and the second data packet, the method further comprises: determining, by the terminal device based on the second frequency band on which the first downlink control information is located, that a HARQ process number corresponding to the first transport block on the first frequency band is the first HARQ process number. receiving, by a terminal device, first downlink control information from a network device, wherein the first downlink control information comprises a first hybrid automatic repeat request HARQ process number; receiving, by the terminal device on a first frequency band, a first data packet carrying a first transport block, and receiving, on a second frequency band, a second data packet carrying a second transport block, wherein the first HARQ process number corresponds to the first transport block on the first frequency band and the second transport block on the second frequency band, and the first transport block is the same as the second transport block; and performing, by the terminal device, joint decoding on the first data packet and the second data packet, wherein the first downlink control information comprises scheduling information of the first data packet and the second data packet; the first frequency band and the second frequency band belong to a first frequency band set, and the first frequency band set comprises at least two frequency bands; the receiving, by the terminal device, first downlink control information from a network device comprises: receiving, by the terminal device on the second frequency band, the first downlink control information from the network device; and before the performing, by the terminal device, joint decoding on the first data packet and the second data packet, the method further comprises: determining, by the terminal device based on the second frequency band on which the first downlink control information is located, that a HARQ process number corresponding to the first transport block on the first frequency band is the first HARQ process number. receiving, by the terminal device on the second frequency band, the first downlink control information from the network device; and before the performing, by the terminal device, joint decoding on the first data packet and the second data packet, the method further comprises: determining, by the terminal device based on the second frequency band on which the first downlink control information is located, that a HARQ process number corresponding to the first transport block on the first frequency band is the first HARQ process number.