Atom transfer radical polymerization technique was used by us to synthesize poly-(2-(dimethylamino) ethyl methacrylate)(PDMAEMA),as a poly cationic electrolyte,PDMAEMA possesses high affinity with the negatively charged polymer electrolyte such as sodium alginate(SA).Then the inorganic salts CaCO3 nanoparticle is introduced into the mixing system.alginate/Ca nanospherical gel was used as the source of alginate molecules and Ca2+ to release all these substances into solution to direct the nucleation and growth of CaCO3 in a CO2 diffusion system.This study shows for the first time that a series of fractal dendritic structures containing calcium carbonate crystals can be obtained from the mixed solution according to the DLA theory.The crystallization of CaCO3 at bottom of the solution is collected to observe as well.I believe the observations reported here can supply a better understanding of the molecular self-assembling nature and be used to develop responsive materials with better performance. Atom transfer radical polymerization technique was used by us to synthesize poly- (2- (dimethylamino) ethyl methacrylate (PDMAEMA), as a poly cationic electrolyte, PDMAEMA possesses high affinity with the negatively charged polymer electrolyte such as sodium alginate (SA). Then the inorganic salts CaCO3 nanoparticle is introduced into the mixing system. Alginate / Ca nanospherical gel was used as the source of alginate molecules and Ca2 + to release all these substances into solution to direct the nucleation and growth of CaCO3 in a CO2 diffusion system. study shows for the first time that a series of fractal dendritic structures containing calcium carbonate crystals can be obtained from the mixed solution according to the DLA theory. The crystallization of CaCO3 at bottom of the solution is collected to observe as well. I believe the observations reported here can supply a better understanding of the molecular self-assembling nature and be used to develop responsive materials with better perf ormance.