Methods, apparatuses and systems are provided for transmitting data. A method includes: sending a target random access preamble to a base station; receiving a target random access response that is sent by the base station based on the target random access preamble and carries repetition-number-indicating information; and transmitting, in accordance with a target transmission repetition number, the target uplink data to the base station during the random access procedure. The target transmission repetition number indicates a number of times the user equipment is configured to repeatedly transmit the target uplink data to the base station during the random access procedure. The target transmission repetition number is determined based on the repetition-number-indicating information and a target transmission block size. The target transmission block size is for the user equipment to transmit the target uplink data to the base station during the random access procedure.