A method of transmitting and receiving downlink information in a wireless communication system supporting Internet of Things (IoT) and a device therefor are disclosed. The method performed by a user equipment (UE) comprises transmitting, to a base station, a physical random access channel (PRACH) preamble, receiving, from the base station, a random access response including an uplink (UL) grant based on the PRACH preamble, transmitting, to the base station, a message 3 based on the UL grant, and receiving, from the base station, a message for contention resolution based on the message 3.