The present disclosure provides a method and device in a User Equipment (UE) and a base station used for wireless communications. The UE receives first information, the first information being used to indicate a first time-domain resource and a second time-domain resource in a first sub-band, wherein the first time-domain resource is reserved for a first radio signal; performs a first access detection to determine whether to transmit the first radio signal on the first time-domain resource in the first sub-band; and transmits the first radio signal on the first time-domain resource in the first sub-band, and does not transmit any radio signal on a reserved time-domain resource in the first sub-band; or, the UE drops transmitting the first radio signal on the first time-domain resource in the first sub-band. The reserved time-domain resource is located between the first time-domain resource and the second time-domain resource in time domain.