Disclosed in the present application are a data transmission method and device. The method comprises: a base station sends a signaling notification to a terminal, so that the terminal determines, according to the signaling notification, whether a pilot signal of data transmitted using a second transmission time interval exists within a first transmission time interval, wherein the first transmission time interval is shorter than the second transmission time interval, or the priority of a service carried by the first transmission time interval is higher than the priority of a service carried by the second transmission time interval, there is a resource overlap between the first transmission time interval and the second transmission time interval, and the terminal using the first transmission time interval for data transmission knows a pilot signal location of the data transmitted using the second transmission time interval; and the base station performing transmission according to a pilot signal resource location of the second transmission time interval. The present application can ensure that a receiving end for other service transmissions can use a pilot signal for data demodulation, thereby avoiding the waste of resources caused by the destruction of the pilot signal.