A method performed by a terminal in a wireless communication system, the method comprising: transmitting a random access preamble to a base station; identifying a random access radio network temporary identifier, RA-RNTI, for receiving a random access response, RAR, message based on an equation; and receiving the RAR message based on the RA-RNTI from the base station, wherein the equation is as follows: RA-RNTI = 1 + t _ id 1 + X 1 ∗ t_id 2 + X 1 ∗ X 2 ∗ f _ id + X 1 ∗ X 2 ∗ Y ∗ c _ id, where t_id1 is an orthogonal frequency division multiplexing, OFDM, symbol related parameter corresponding to an index of a first OFDM symbol of a PRACH transmission occasion in which the random access preamble is transmitted, t_id2 is a slot related parameter corresponding to an index of a first slot of the PRACH transmission occasion, f_id is a frequency related parameter corresponding to an index of the PRACH transmission occasion in a frequency domain, c_id is an uplink carrier related parameter, X1 is a number of OFDM symbols in a slot, X2 is a maximum number of slots in a radio frame, and Y depends on a number of RACH transmission occasions supported in the frequency domain, and wherein the uplink carrier related parameter indicates whether the random access preamble is transmitted on a supplemental uplink carrier or not. transmitting a random access preamble to a base station; identifying a random access radio network temporary identifier, RA-RNTI, for receiving a random access response, RAR, message based on an equation; and receiving the RAR message based on the RA-RNTI from the base station, wherein the equation is as follows: RA-RNTI = 1 + t _ id 1 + X 1 ∗ t_id 2 + X 1 ∗ X 2 ∗ f _ id + X 1 ∗ X 2 ∗ Y ∗ c _ id, where t_id1 is an orthogonal frequency division multiplexing, OFDM, symbol related parameter corresponding to an index of a first OFDM symbol of a PRACH transmission occasion in which the random access preamble is transmitted, t_id2 is a slot related parameter corresponding to an index of a first slot of the PRACH transmission occasion, f_id is a frequency related parameter corresponding to an index of the PRACH transmission occasion in a frequency domain, c_id is an uplink carrier related parameter, X1 is a number of OFDM symbols in a slot, X2 is a maximum number of slots in a radio frame, and Y depends on a number of RACH transmission occasions supported in the frequency domain, and wherein the uplink carrier related parameter indicates whether the random access preamble is transmitted on a supplemental uplink carrier or not. where t_id1 is an orthogonal frequency division multiplexing, OFDM, symbol related parameter corresponding to an index of a first OFDM symbol of a PRACH transmission occasion in which the random access preamble is transmitted, t_id2 is a slot related parameter corresponding to an index of a first slot of the PRACH transmission occasion, f_id is a frequency related parameter corresponding to an index of the PRACH transmission occasion in a frequency domain, c_id is an uplink carrier related parameter, X1 is a number of OFDM symbols in a slot, X2 is a maximum number of slots in a radio frame, and Y depends on a number of RACH transmission occasions supported in the frequency domain, and wherein the uplink carrier related parameter indicates whether the random access preamble is transmitted on a supplemental uplink carrier or not.