Nano- and micro-sized calcium carbonate (CaCO3) with various morphologies including multi-petal-flower-shaped, multi-step-cube-shaped, coral-shaped, dendrite-shaped and multi-antenna-shaped was successfully prepared using dodecyltrimethylammonium bromide (DTAB) micellar vevulsant. The effects of temperature, pH and the concentration of DTAB micellar solution on the morphology and crystalline form of CaCO3 were systematically investigated. The prepared CaCO3 was characterized by Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). The concentration of DTAB micelle, pH and reaction temperature are found to play crucial roles in the morphology, size and crystalline form of the final products. On the base of the characterizations, a possible self-assembled mechanism was proposed. The novel multi-petal-flower-shaped and multi-antenna-shaped CaCO3 may have some unique properties and potential applications in the future. (C) 2010 Elsevier B.V. All rights reserved.