A feedback information sending method performed by an apparatus (116, 1000), the method comprising: receiving, in a first time unit, a first reference signal sent by a network device, wherein the first reference signal corresponds to first downlink control information, and the first downlink control information is used to schedule a first information block; determining, based on the first reference signal, that receiving of the first downlink control information in the first time unit fails; and sending, on a first resource corresponding to the first time unit, third feedback information to the network device; wherein the first resource is used to send at least two information bits, and a first status of the at least two information bits is used to indicate first feedback information, wherein the first feedback information indicates that the receiving of the first downlink control information fails; a second status of the at least two information bits is used to indicate second feedback information, the second feedback information is used to indicate a transmission parameter adjustment value, and the transmission parameter adjustment value is determined by the terminal device based on a second reference signal received in the first time unit; a third status of the at least two information bits is used to indicate third feedback information, the third feedback information is used to indicate that the terminal device correctly decodes the first information block received in a time unit m-s, the first time unit is a time unit m, m and s are positive integers, and m is greater than s, the first information block received in a time unit m-s being a previous transmission of the first information block scheduled by the first downlink control information associated with the first reference signal received in the time unit m; and the sending, by the terminal device, third feedback information comprises: sending, by the terminal device, on the first resource, the third status. receiving, in a first time unit, a first reference signal sent by a network device, wherein the first reference signal corresponds to first downlink control information, and the first downlink control information is used to schedule a first information block; determining, based on the first reference signal, that receiving of the first downlink control information in the first time unit fails; and sending, on a first resource corresponding to the first time unit, third feedback information to the network device; wherein the first resource is used to send at least two information bits, and a first status of the at least two information bits is used to indicate first feedback information, wherein the first feedback information indicates that the receiving of the first downlink control information fails; a second status of the at least two information bits is used to indicate second feedback information, the second feedback information is used to indicate a transmission parameter adjustment value, and the transmission parameter adjustment value is determined by the terminal device based on a second reference signal received in the first time unit; a third status of the at least two information bits is used to indicate third feedback information, the third feedback information is used to indicate that the terminal device correctly decodes the first information block received in a time unit m-s, the first time unit is a time unit m, m and s are positive integers, and m is greater than s, the first information block received in a time unit m-s being a previous transmission of the first information block scheduled by the first downlink control information associated with the first reference signal received in the time unit m; and the sending, by the terminal device, third feedback information comprises: sending, by the terminal device, on the first resource, the third status.