The disclosure discloses a method and device in UE and a base station for channel coding. A first node first determines a first bit block and then transmits a first radio signal, wherein bits of the first bit block are used to generate bits of a second bit block, a third bit block comprises bits of the second bit block and the first bit block, and the third bit block is used to generate the first radio signal. The first bit block, the second bit block and the third bit block comprise P1, P2 and P3 bits, respectively.