A data communication method of a user equipment includes receiving a higher layer signal indicating a change of a determination standard of a start symbol to which a physical downlink shared channel (PDSCH) is assigned, detecting a downlink control information (DCI) format including PDSCH scheduling information from a physical downlink control channel (PDCCH), and determining the start symbol to which the PDSCH is assigned, based on at least one of information about the DCI format, mapping type information of the PDSCH, or an offset value between a slot in which the PDCCH is located and a slot in which the PDSCH is located.