A communication method and apparatus relate to the field of communication technologies, to enable a network device to support communication of a new type of terminal device without additionally sending a set of complete system information. The method includes: The network device sends a SIB1 and supplementary information. Maximum transmission bandwidth of a first terminal device is different from that of a second terminal device. The supplementary information includes first information and/or second information, the SIB1 does not include the first information, and a parameter value of the second information included in the supplementary information is different from a parameter value of the second information included in the SIB1. After receiving the SIB1 and the supplementary information, the second terminal device accesses a network based on partial information other than the second information in the SIB1 and the supplementary information. Consumed resources for downlink transmission can be reduced.