A transmission direction configuration method carried out by a terminal device, comprising: receiving initial configuration information from a network device through a radio resource control, RRC, signaling, wherein the initial configuration information comprises a correspondence between at least one index value and at least one corresponding transmission directions configuration of an indexed list of transmission directions configuration; receiving first indication information from the network device through a physical downlink control channel, PDCCH, wherein the first indication information comprises an index value of the at least one index value, wherein the at least one transmission directions configuration of an indexed list of transmission directions configuration is used to indicate a configuration of uplink and/or downlink transmission directions, the configuration is used to describe types, a number and distribution of resource elements comprised in each period in a time duration that is indicated by a parameter and that starts from the time point indicated by the first indication information, wherein the time duration includes N periods, wherein N is a positive integer, the resource element is a resource that is obtained through division based on a resource granularity, the resource granularity comprises a time domain granularity, the time domain granularity comprises an orthogonal frequency division multiplexing, OFDM, symbol, the types of the resource elements comprise an uplink resource element, a downlink resource element, and a switch resource element between the downlink resource element and the uplink resource element, a transmission direction of the uplink resource element is an uplink direction, and a transmission direction of the downlink resource element is a downlink direction; and performing information transmission or a configuration operation based on the configuration, indicated by the first indication information, of the uplink and/or downlink transmission directions. receiving initial configuration information from a network device through a radio resource control, RRC, signaling, wherein the initial configuration information comprises a correspondence between at least one index value and at least one corresponding transmission directions configuration of an indexed list of transmission directions configuration; receiving first indication information from the network device through a physical downlink control channel, PDCCH, wherein the first indication information comprises an index value of the at least one index value, wherein the at least one transmission directions configuration of an indexed list of transmission directions configuration is used to indicate a configuration of uplink and/or downlink transmission directions, the configuration is used to describe types, a number and distribution of resource elements comprised in each period in a time duration that is indicated by a parameter and that starts from the time point indicated by the first indication information, wherein the time duration includes N periods, wherein N is a positive integer, the resource element is a resource that is obtained through division based on a resource granularity, the resource granularity comprises a time domain granularity, the time domain granularity comprises an orthogonal frequency division multiplexing, OFDM, symbol, the types of the resource elements comprise an uplink resource element, a downlink resource element, and a switch resource element between the downlink resource element and the uplink resource element, a transmission direction of the uplink resource element is an uplink direction, and a transmission direction of the downlink resource element is a downlink direction; and performing information transmission or a configuration operation based on the configuration, indicated by the first indication information, of the uplink and/or downlink transmission directions.