The invention provides a cell searching method and device in LAA communication. In the first step, a base station sends a first signaling indication configuration parameter on a first carrier, and theconfiguration parameter is used for assisting in determining a first frequency domain resource; or determining the first frequency domain resource according to a predetermined criterion. In the step2, the base station sends a first sequence group in a first frequency domain resource in a first time window on a second carrier wave. According to the scheme provided by the invention, the UE can detect the PCI conflict and report the PCI conflict to the serving base station so as to avoid inter-cell interference caused by the PCI conflict. The method is compatible with the existing LTE protocolas much as possible, and has relatively good compatibility.