Calcium carbonate in the crystal form of vaterite can be expected as a coating pigment because of fineness of primary particles and the spherical secondary structure. So far, the interfacial reaction method has been applied to prepare vaterite particles. However, to avoid using volatile organic solvents, an aqueous system with no organic solvent was developed in this study. Consequently, vaterite was successfully synthesized from only two aqueous solutions of potassium carbonate and calcium chloride with no additive. As parameters of the reaction condition, temperature, agitation rate and effects of surfactants were examined. The optimum temperature of the reacting liquids was around 40 °C. Reduced volumes of the reacting liquids to intensify the agitation effect increased the vaterite ratio for a given homogenizer at a constantly rotating speed. Among surfactants used, there was no difference observed in the effect on vaterite generation. At a suitable condition about other parameters, pure vaterite was obtained even under no surfactant condition. In summary, it was speculated that the vaterite form was generated at an early stage of the reaction. At insufficient levels of shear stress, vaterite growth is not promoted and generated vaterite transfers spontaneously to calcite. Surfactants are assumed to adsorb onto surfaces of primary particles and trigger an orderly aggregation.