A method and device for sending an HARQ-ACK codebook, and a method and device for receiving an HARQ-ACK codebook are provided. The sending method includes: a first device generating an HARQ-ACK codebook, the HARQ-ACK codebook including a first part and a second part, the first part including TB based HARQ-ACK information, the second part including CBG based HARQ-ACK information of n TBs, and the number of bits of the second part being determined in advance, n being a positive integer; and the first device sending the HARQ-ACK codebook to a second device.