A communication method performed by a communication apparatus, the method comprising: transmitting, to a terminal device, information about a control resource set, wherein the control resource set consists of K resource blocks, RBs, in frequency domain and one or more symbols in time domain, the K RBs and the one or more symbols form M resource element groups, REGs, each of the M REGs consists of one RB and one symbol, and wherein indexes of the M REGs are obtained by numbering the M REGs consecutively in an increasing order in a time-first manner, K and M are positive integer; determining one or more control channel elements, CCEs, wherein each of the one or more CCEs consists of at least one first REG bundle, a quantity of first REGs included in any first REG bundle in the at least one first REG bundle is L, L RBs corresponding to the L first REGs included in the any first REG bundle are consecutive in time domain and/or frequency domain and belong to the M REGs, and L is an integer greater than 1; and sending a control channel to the terminal device by using the one or more CCEs, wherein the method further comprises: performing interleaving on at least one REG bundle index, to obtain the at least one first REG bundle, L is used as an interleaving granularity, wherein REGs included in any of at least one REG bundle corresponding to the at least one REG bundle index belong to the M REGs; and determining interleaved REG indexes of the L first REGs based on the indexes of the interleaved first REG bundle. transmitting, to a terminal device, information about a control resource set, wherein the control resource set consists of K resource blocks, RBs, in frequency domain and one or more symbols in time domain, the K RBs and the one or more symbols form M resource element groups, REGs, each of the M REGs consists of one RB and one symbol, and wherein indexes of the M REGs are obtained by numbering the M REGs consecutively in an increasing order in a time-first manner, K and M are positive integer; determining one or more control channel elements, CCEs, wherein each of the one or more CCEs consists of at least one first REG bundle, a quantity of first REGs included in any first REG bundle in the at least one first REG bundle is L, L RBs corresponding to the L first REGs included in the any first REG bundle are consecutive in time domain and/or frequency domain and belong to the M REGs, and L is an integer greater than 1; and sending a control channel to the terminal device by using the one or more CCEs, wherein the method further comprises: performing interleaving on at least one REG bundle index, to obtain the at least one first REG bundle, L is used as an interleaving granularity, wherein REGs included in any of at least one REG bundle corresponding to the at least one REG bundle index belong to the M REGs; and determining interleaved REG indexes of the L first REGs based on the indexes of the interleaved first REG bundle. performing interleaving on at least one REG bundle index, to obtain the at least one first REG bundle, L is used as an interleaving granularity, wherein REGs included in any of at least one REG bundle corresponding to the at least one REG bundle index belong to the M REGs; and determining interleaved REG indexes of the L first REGs based on the indexes of the interleaved first REG bundle.