Ultrafine calcim carbonate powders with the size of $0.05~0.1;{mu}m$ and the calcite phase were synthesized by the nozzle spouting method, which could be only obtained when high calcium ion concentration within slurry was maintained at the beginning of the reaction. But, in the regions of low ${Ca(OH)}_2$ concentration (0.5~1.0 wt%) or high ${Ca(OH)}_2$ concentration (<3.0 wt%), synthesized calcium carbonate powder was shown the large particle size with agglomeration. To obtain ultrafine calcium carbonate powder in this region, the methods of slurry circuation and $CO_{2}$ gas supply were changed during reaction. Resultly, it was possible to synthesize ultrafine particles (${approx}0.05{mu} extrm{m}$)in the regions of low ${Ca(OH)}_2$ concentration (${approx}0.5wt%$) and high ${Ca(OH)}_2$ concentration (${approx}0.5wt%$), which can not be obtained the fine calcium carbonate powder still now.