The thin-slab structure with a new form of phononic crystals is constructed. The mechanism and influencing factors of band gap are analyzed. The influence of power change on vibration reduction of phononic crystal plate is studied. Three complete phononic band gaps are obtained. The bandwidth of the second band gap reaches 850 Hz. As the height of the prism increases， the bandwidth of the three bandgap begins to widen. The power of the prism increases， the start and end frequencies of the band gap de? crease， while the increase of the edge thickness weakens the energy focusing effect and gradually narrows the bandwidth of the band gap. By using the linear defect and band gaps of phononic crystals， the waveguide effect of thin-slab structure with phononic crystals is achieved. The study provides a new concept to manipulate the flexural wave of thin-slab structure.