Abstract: The vigor and rooting of plantlets derived from microspore culture of maize could be obviously improved by adding 1.0mg/L IBA, 0.05mg/L NAA, 1mg/l MET to rooting medium. The transplanting survival rate of plantlets could be increased to 90% through the procedure of hardening plantlets for 24~48h, growing of 5~7d with medium of perlit or vermiculite and then transplanting them to soil supplemented with 1/3 chicken excrement thoroughly decomposed. The survived plants with deep grown color-leaves and vigor roots could grow strongly in the field. The method for measurement of the length of stoma guard cell was proved to be a simple way of estimating ploidy of the regenerated plants.