Provided are a dynamic resource allocation method and device, a base station and a terminal. The method comprises: a base station acquiring resource allocation information about downlink data and / or uplink data indicated by downlink control signalling, wherein the resource allocation information comprises the location and number of resource allocation elements (RAEs); the RAEs comprise N transmission symbols in a time domain; and the RAEs completely occupy the full bandwidth in a frequency domain, or each RAE occupies one BP among X bandwidth parts (BPs) in the frequency domain, the X BPs forming the frequency domain, where N is an integer greater than 0, and X is an integer greater than 1; and the base station sending the resource allocation information to a terminal. By means of the technical solution provided in the present invention, the problems in the related art that it is not possible to use an LTE control channel to schedule uplink and downlink services of a plurality of transmission symbols on a high-frequency carrier and the transmission of uplink services, and that the overhead of control signalling is relatively high in a network independently networked by an LTE carrier and the high-frequency carrier and the like are solved, thus achieving that the LTE carrier schedules the high-frequency carrier across carriers.