This paper deals with the effects of magnetic water on the quality of Rice seedling and inquires into the mechanism. The growth of Rice seedling both above and under ground was significantly promoted by magnetic water, it appeared to increase the root numbers（0.2-19.5%）, root length（0.8-60.9%）, plant height, leave numbers, stem thickness, 100 dried plants weight （2.7-9%）percentage of tiller（7-21%）,and the Rice seedlings stress resistance was increased too.
The cause of magnetic water promoting the quality of Rice seedling is attributable to the increase of nitrate reductase activity, retaining water ability of leaves, chlorophyll content, bound water, absorption of N. P. K and the decrease of Permeability of cell membrane.