A user equipment in a wireless communication system receives RACH configuration information including preamble format information indicating a first format and transmits a RACH preamble with the first format. The RACH preamble with the first format includes a cyclic prefix (CP) part and a sequence part in a time domain. The RACH preamble with the first format satisfies: a CP length of the RACH preamble of the first format is N times a CP length NCP of an orthogonal frequency division multiplexing (OFDM) symbol, where N is the number of OFDM symbols used to transmit a RACH preamble and is greater than 1.