Ultrafine　CaCO3　was　continuously　prepared　in　a　spouted　bed　reactor　of　42　mm　I.D.　In　the　reactor,　glass　beads　of　average　diameter　1.2　mm　and　density　2510　kg·m-3　were　used　as　inert　particles,　which　provide　great　surface　for　mass　and　heat　transfer.　Effects　of　operating　variables　such　as　CO3　concentration,　initial　concentration　of　Ca(OH)2,　reaction　temperature　and　static　bed　height　on　conversion　of　Ca(OH)2　and　particles　size　of　produced　CaCO3　were　experimentally　investigated.　The　results　show　that　the　cube-shaped　particles　of　CaCO3　with　mean　size　80　nm　and　water-containing　less　than　0.15%　are　obtained　by　this　one-step　novel　technology　-　an　integrated　reaction-drying　technology　for　producing　ultrafine　CaCO3.