A method for determining a size of transport blocks in a subframe, the method comprising: providing a transport block size table, wherein the columns indicate the number of allocated physical resource blocks, the rows indicate a transport block size index, and the elements of the table provide the transport block size; acquiring the number of physical resource blocks N' PRB and the transport block size index I' TBS; determining a conversion relationship, and converting the values N' PRB and I' TBS, according to the conversion relationship, respectively into the converted values N PRB and I TBS to be used in existing calculation for the size of transport blocks (S 102); and using the transport block size table to calculate the size of the transport blocks according to the converted values N PRB and I TBS; wherein determining the conversion relationship in the present transmission scheme according to a corresponding relationship between a transmission scheme and a conversion relationship, comprises at least one of following: when a physical downlink shared channel bearing the transport blocks starts to transmit data from a first orthogonal frequency division multiplexing symbol in a time domain of a subframe, and/or, when a subframe transmitting the transport blocks does not send a cell-specific reference signal, the conversion relationship is: I TBS = I ' TBS, N PRB = min floor N ' PRB ∗ A, 110, 1 < A ≤ 2, or, N PRB = N PRB, I TBS = min floor I ' TBS ∗ B, 26, 1 < B ≤ 2; when resource elements of the physical downlink shared channel bearing the transport blocks are muted, the conversion relationship is: I TBS = I ' TBS, N PRB = min floor N ' PRB ∗ A, 1, 1 / 2 ≤ A ≤ 1; or, N PRB = N PRB, I TBS = max floor I ' TBS ∗ B, 1, 1 / 2 ≤ B<1; if the number of orthogonal frequency division multiplexing symbols in a downlink pilot time slot,DwPTS, of a special subframe is 6 or 5, the conversion relationship is: I TBS = I ' TBS, N PRB = max ⌊ N PRB ' × A ⌋, 1, where 0 ≤ A < 3/4, or, N PRB = N PRB ', I TBS = max ⌊ I ' TBS × B ⌋, 1, where 0 ≤ B ≤ 3/4; when 0 ≤ A ≤ 1, the parameter A is one of the following: 1/5, 1/4, 1/3, 1/2, 2/3 and 3/5. providing a transport block size table, wherein the columns indicate the number of allocated physical resource blocks, the rows indicate a transport block size index, and the elements of the table provide the transport block size; acquiring the number of physical resource blocks N' PRB and the transport block size index I' TBS; determining a conversion relationship, and converting the values N' PRB and I' TBS, according to the conversion relationship, respectively into the converted values N PRB and I TBS to be used in existing calculation for the size of transport blocks (S 102); and using the transport block size table to calculate the size of the transport blocks according to the converted values N PRB and I TBS; wherein determining the conversion relationship in the present transmission scheme according to a corresponding relationship between a transmission scheme and a conversion relationship, comprises at least one of following: when a physical downlink shared channel bearing the transport blocks starts to transmit data from a first orthogonal frequency division multiplexing symbol in a time domain of a subframe, and/or, when a subframe transmitting the transport blocks does not send a cell-specific reference signal, the conversion relationship is: I TBS = I ' TBS, N PRB = min floor N ' PRB ∗ A, 110, 1 < A ≤ 2, or, N PRB = N PRB, I TBS = min floor I ' TBS ∗ B, 26, 1 < B ≤ 2; when resource elements of the physical downlink shared channel bearing the transport blocks are muted, the conversion relationship is: I TBS = I ' TBS, N PRB = min floor N ' PRB ∗ A, 1, 1 / 2 ≤ A ≤ 1; or, N PRB = N PRB, I TBS = max floor I ' TBS ∗ B, 1, 1 / 2 ≤ B<1; if the number of orthogonal frequency division multiplexing symbols in a downlink pilot time slot,DwPTS, of a special subframe is 6 or 5, the conversion relationship is: I TBS = I ' TBS, N PRB = max ⌊ N PRB ' × A ⌋, 1, where 0 ≤ A < 3/4, or, N PRB = N PRB ', I TBS = max ⌊ I ' TBS × B ⌋, 1, where 0 ≤ B ≤ 3/4; when 0 ≤ A ≤ 1, the parameter A is one of the following: 1/5, 1/4, 1/3, 1/2, 2/3 and 3/5. when a physical downlink shared channel bearing the transport blocks starts to transmit data from a first orthogonal frequency division multiplexing symbol in a time domain of a subframe, and/or, when a subframe transmitting the transport blocks does not send a cell-specific reference signal, the conversion relationship is: I TBS = I ' TBS, N PRB = min floor N ' PRB ∗ A, 110, 1 < A ≤ 2, or, N PRB = N PRB, I TBS = min floor I ' TBS ∗ B, 26, 1 < B ≤ 2; when resource elements of the physical downlink shared channel bearing the transport blocks are muted, the conversion relationship is: I TBS = I ' TBS, N PRB = min floor N ' PRB ∗ A, 1, 1 / 2 ≤ A ≤ 1; or, N PRB = N PRB, I TBS = max floor I ' TBS ∗ B, 1, 1 / 2 ≤ B<1; if the number of orthogonal frequency division multiplexing symbols in a downlink pilot time slot,DwPTS, of a special subframe is 6 or 5, the conversion relationship is: I TBS = I ' TBS, N PRB = max ⌊ N PRB ' × A ⌋, 1, where 0 ≤ A < 3/4, or, N PRB = N PRB ', I TBS = max ⌊ I ' TBS × B ⌋, 1, where 0 ≤ B ≤ 3/4; when 0 ≤ A ≤ 1, the parameter A is one of the following: 1/5, 1/4, 1/3, 1/2, 2/3 and 3/5.