A method and device in user equipment and a base station for wireless communication is disclosed. The base station equipment sequentially generates a first information block including bits in a first sub-information-block and a second sub-information-block, performs first channel coding and transmits a first radio signal. The first bit block includes bits in the first information block, the first bit block is used as an input of the first channel coding, the value of the first sub-information-block is related to the number of padding bits, and the relative position of the first sub-information-block and the second sub-information-block in the first information block is related to the number of bits included in the first information block. The present disclosure utilizes the characteristics of serial decoding of a Polar code, and improves the decoding performance using padding bits as frozen bits through the internal indication of the code block.