A secondary cell control method, comprising: receiving control information in a time unit n, wherein the control information comprises an activation command for a first secondary cell; and sending first information of the first secondary cell in a time unit n+ k, wherein k is determined based on a first frame structure parameter configured for a terminal device, and both n and k are positive integers; characterized in that an index of the first frame structure parameter is: a smaller value in a frame structure parameter index of the first secondary cell and a frame structure parameter index of a second secondary cell, wherein the control information further comprises an activation command or a deactivation command for the second secondary cell; a smallest value in frame structure parameter indexes of a cell that are configured for the terminal device; a smallest value in a frame structure parameter index of the first secondary cell, a frame structure parameter index of a second secondary cell, and a frame structure parameter index of a cell used to transmit the first information, wherein the control information further comprises an activation command or a deactivation command for the second secondary cell; or a frame structure parameter with a smaller index value in a second frame structure parameter and a frame structure parameter that corresponds to a cell used to transmit the control information. receiving control information in a time unit n, wherein the control information comprises an activation command for a first secondary cell; and sending first information of the first secondary cell in a time unit n+ k, wherein k is determined based on a first frame structure parameter configured for a terminal device, and both n and k are positive integers; characterized in that an index of the first frame structure parameter is: a smaller value in a frame structure parameter index of the first secondary cell and a frame structure parameter index of a second secondary cell, wherein the control information further comprises an activation command or a deactivation command for the second secondary cell; a smallest value in frame structure parameter indexes of a cell that are configured for the terminal device; a smallest value in a frame structure parameter index of the first secondary cell, a frame structure parameter index of a second secondary cell, and a frame structure parameter index of a cell used to transmit the first information, wherein the control information further comprises an activation command or a deactivation command for the second secondary cell; or a frame structure parameter with a smaller index value in a second frame structure parameter and a frame structure parameter that corresponds to a cell used to transmit the control information. a smaller value in a frame structure parameter index of the first secondary cell and a frame structure parameter index of a second secondary cell, wherein the control information further comprises an activation command or a deactivation command for the second secondary cell; a smallest value in frame structure parameter indexes of a cell that are configured for the terminal device; a smallest value in a frame structure parameter index of the first secondary cell, a frame structure parameter index of a second secondary cell, and a frame structure parameter index of a cell used to transmit the first information, wherein the control information further comprises an activation command or a deactivation command for the second secondary cell; or a frame structure parameter with a smaller index value in a second frame structure parameter and a frame structure parameter that corresponds to a cell used to transmit the control information.