This application relates to the field of communications technologies and discloses a signal transmission method and device, and a system. The method includes: determining, by a first device after receiving first information transmitted by a second device, to perform at least one of interference measurement and channel measurement on a resource, or to transmit a reference signal on a resource. The second device can configure the resource of the reference signal for the first device by transmitting the first information to the first device that is in a transmitting state or a receiving state, thereby improving flexibility of resource configuration of the reference signal. When this technical solution is applied to cross interference measurement, accuracy of inter-UE interference measurement is improved.