Provided are a resource information sending method and apparatus, and a resource information receiving method and apparatus. The resource information sending method comprises: a first terminal device carrying out sensing, to obtain a reserved first resource, a reference signal received power (RSRP) corresponding to the first resource, and a receiving priority; determining, from the first resource, a second resource that needs to be sent to a second terminal device, and determining reference signal received power (RSRP) indication information according to a reference signal received power (RSRP) corresponding to the second resource; and the first terminal device sending auxiliary information to the second terminal device, wherein the auxiliary information comprises the second resource and the reference signal received power (RSRP) indication information.