Embodiments of this application disclose a message transmission method and apparatus, a terminal, and a base station. In the method, a symbol or symbol group may be used as a granularity to select a plurality of symbols or symbol groups from one or more slots and then allocate the plurality of symbols or symbol groups to a same terminal for transmitting data. The plurality of symbols or symbol groups may be used for uplink data scheduling or may be used for downlink data scheduling. Therefore, a slot resource is allocated at a small granularity, so that a time domain resource is more flexibly allocated, and the slot resource is more fully utilized. This helps improve message transmission efficiency, thereby expanding a coverage area.