On the basis of laser field and band interactions between liquid molecules, ft layered vaporatizion model of liquid surface under the action of the laser light is suggested, and a theoretical formula for layered vaporation is derived. Irradiating the surfaces of water, acetone and alcohol with COs laser light at 10. 6um, the time for surface vaporization of layers are measured to be 1.28 x 10-3s,9.57 x 10-4 s and 1.05 X 10-3 s respetively. Experimental results confirm the theory.