This specification provides a method of transmitting and receiving data in a wireless communication system and an apparatus therefor. Specifically, a method for transmitting and receiving data in a wireless communication system by a user equipment includes receiving downlink control information from a base station and receiving downlink data from the base station through a downlink shared channel configured based on the downlink control information, wherein when the downlink data is broadcasted, a bundling size for the downlink shared channel is configured as a pre-defined value.