A method for determining a number of decoder iterations in a 4G or 5G mobile communication system, comprising: determining virtual code blocks of a newly transmitted transport block and a retransmitted transport block to be processed by a decoder within a time slot; classifying the virtual code blocks according to whether the transport block corresponding to the virtual code block is the newly transmitted transport block, or, according to a retransmitted error rate of the retransmitted transport block; and determining the number of iterations for each type of virtual code blocks in the decoder; wherein, the determining virtual code blocks of a newly transmitted transport block and a retransmitted transport block to be processed by a decoder within a time slot comprises: calculating the number of code blocks contained in the newly transmitted transport block, and multiplying the number of code blocks, contained in the newly transmitted transport block, by a first virtual factor to obtain the number of virtual code blocks of the newly transmitted transport block, the first virtual factor is calculated or configured based on a proportion of a time duration, actually occupied by the code blocks to be decoded in the newly transmitted transport block, in the time slot; and calculating positions and the number of code blocks actually to be processed for the retransmitted transport block, and multiplying the number of code blocks, actually to be processed for the retransmitted transport block, by a second virtual factor to obtain the number of virtual code blocks of the retransmitted transport block, the second virtual factor is calculated or configured base on a proportion of a time duration, actually occupied by the code blocks actually to be processed for the retransmitted transport block, in the time slot, the code blocks actually to be processed for the retransmitted transport block are code blocks which were previously decoded erroneously. determining virtual code blocks of a newly transmitted transport block and a retransmitted transport block to be processed by a decoder within a time slot; classifying the virtual code blocks according to whether the transport block corresponding to the virtual code block is the newly transmitted transport block, or, according to a retransmitted error rate of the retransmitted transport block; and determining the number of iterations for each type of virtual code blocks in the decoder; wherein, the determining virtual code blocks of a newly transmitted transport block and a retransmitted transport block to be processed by a decoder within a time slot comprises: calculating the number of code blocks contained in the newly transmitted transport block, and multiplying the number of code blocks, contained in the newly transmitted transport block, by a first virtual factor to obtain the number of virtual code blocks of the newly transmitted transport block, the first virtual factor is calculated or configured based on a proportion of a time duration, actually occupied by the code blocks to be decoded in the newly transmitted transport block, in the time slot; and calculating positions and the number of code blocks actually to be processed for the retransmitted transport block, and multiplying the number of code blocks, actually to be processed for the retransmitted transport block, by a second virtual factor to obtain the number of virtual code blocks of the retransmitted transport block, the second virtual factor is calculated or configured base on a proportion of a time duration, actually occupied by the code blocks actually to be processed for the retransmitted transport block, in the time slot, the code blocks actually to be processed for the retransmitted transport block are code blocks which were previously decoded erroneously. calculating the number of code blocks contained in the newly transmitted transport block, and multiplying the number of code blocks, contained in the newly transmitted transport block, by a first virtual factor to obtain the number of virtual code blocks of the newly transmitted transport block, the first virtual factor is calculated or configured based on a proportion of a time duration, actually occupied by the code blocks to be decoded in the newly transmitted transport block, in the time slot; and calculating positions and the number of code blocks actually to be processed for the retransmitted transport block, and multiplying the number of code blocks, actually to be processed for the retransmitted transport block, by a second virtual factor to obtain the number of virtual code blocks of the retransmitted transport block, the second virtual factor is calculated or configured base on a proportion of a time duration, actually occupied by the code blocks actually to be processed for the retransmitted transport block, in the time slot, the code blocks actually to be processed for the retransmitted transport block are code blocks which were previously decoded erroneously.