A method of determining a transmission parameter of a data shared channel for narrow band-internet of things, NB-IoT, comprising: receiving downlink control information, the downlink control information comprising a field configured to determine a transmission parameter of a data shared channel, the transmission parameter comprising at least one of a modulation mode, a transmission block size, TBS, a sequence length upon rate matching and a repetition number, the field comprising at least one of a modulation and coding scheme, MCS, indicator field, a resource allocation field and a repetition number indicator field, the MCS indicator field being configured to indicate a modulation and coding scheme, the resource allocation field being configured to indicate information of resource allocation of a transmission block, TB, based on a resource unit, RU, the repetition number indicator field being configured to indicate a number of repetitive transmission; and determining the transmission parameter according to the field, characterized in that, determining the transmission parameter according to the field comprises: determining the TBS according to the field and a preset TBS table, and before determining the TBS according to the field and a preset TBS table, determining the preset TBS table by: using a first TBS table as the preset TBS table under a first condition, and using a second TBS table as the preset TBS table under a second condition, wherein the first TBS table and the second TBS table are different TBS tables, wherein the first condition and the second condition comprise at least one of: the first condition being uplink, single-tone frequency multiple access, while the second condition being uplink, multi-tone frequency multiple access; the first condition being uplink, single-tone frequency multiple access, while the second condition being downlink, OFDMA multiple access; the first condition being an in-band operation mode, while the second condition being a stand-alone operation mode or a guard-band operation mode. receiving downlink control information, the downlink control information comprising a field configured to determine a transmission parameter of a data shared channel, the transmission parameter comprising at least one of a modulation mode, a transmission block size, TBS, a sequence length upon rate matching and a repetition number, the field comprising at least one of a modulation and coding scheme, MCS, indicator field, a resource allocation field and a repetition number indicator field, the MCS indicator field being configured to indicate a modulation and coding scheme, the resource allocation field being configured to indicate information of resource allocation of a transmission block, TB, based on a resource unit, RU, the repetition number indicator field being configured to indicate a number of repetitive transmission; and determining the transmission parameter according to the field, characterized in that, determining the transmission parameter according to the field comprises: determining the TBS according to the field and a preset TBS table, and before determining the TBS according to the field and a preset TBS table, determining the preset TBS table by: using a first TBS table as the preset TBS table under a first condition, and using a second TBS table as the preset TBS table under a second condition, wherein the first TBS table and the second TBS table are different TBS tables, wherein the first condition and the second condition comprise at least one of: the first condition being uplink, single-tone frequency multiple access, while the second condition being uplink, multi-tone frequency multiple access; the first condition being uplink, single-tone frequency multiple access, while the second condition being downlink, OFDMA multiple access; the first condition being an in-band operation mode, while the second condition being a stand-alone operation mode or a guard-band operation mode. using a first TBS table as the preset TBS table under a first condition, and using a second TBS table as the preset TBS table under a second condition, wherein the first TBS table and the second TBS table are different TBS tables, wherein the first condition and the second condition comprise at least one of: the first condition being uplink, single-tone frequency multiple access, while the second condition being uplink, multi-tone frequency multiple access; the first condition being uplink, single-tone frequency multiple access, while the second condition being downlink, OFDMA multiple access; the first condition being an in-band operation mode, while the second condition being a stand-alone operation mode or a guard-band operation mode. the first condition being uplink, single-tone frequency multiple access, while the second condition being uplink, multi-tone frequency multiple access; the first condition being uplink, single-tone frequency multiple access, while the second condition being downlink, OFDMA multiple access; the first condition being an in-band operation mode, while the second condition being a stand-alone operation mode or a guard-band operation mode.