The J×B heating mechanism of plasma under the radiation of non-relativistic linearly polarized laser light is studied analytically and a self-consistent theory including the effects of two kinds of ponderomotive forces is developed. Meanwhile, the J×B heating mechanism with the density profile modification is discussed, and the relation curve of the corresponding absorption coefficient vis the laser intensity is obtained. The result shows that the absorption coefficient fabs owing to the J×B heating is about 2.8% when the laser intensity factor A0＝20.