When Shape memory alloy (SMA) wires are embedded in the composite structure with a specific volume fraction, the properties of the resulting hybrid composite structure, which is called SMA-reinforced composite structure, will be reinforced. Some of SMA wires embedded in the composite can be viewed as two electrodes of the capacitor. The deformation of the composite structure will cause change of the capacitor, therefore the segmental SMA wires embedded in the composite may be considered as the self-sensitive element of structure strain monitoring. The measurement circuit monitoring the change of micro capacitor in structure is designed, and it is integrated with radio frequency identification (RFID) technology to compose RFID sensor-tag, and the variation of capacitor is send to the RFID reader wirelessly to form a wireless health monitoring system. Experimental results show that this RFID sensor-tag and its system can be feasibly used in wireless structural health monitoring of SMA-reinforced composite structure.