One-dimensional cobalt complex ([(NH3)(4)Co(OH)(2)Co(NH3)(4)]Cl-4(H2O)(4)) was successfully prepared by using a simple CTAB-mediated microemulsion method in a xylene-ethanol-water system. Experiments were designed to investigate the morphologies of samples in different cetyltrimethyl ammonium bromide (CTAB) concentration. The diameter decrease and the aspect ratio of as-product increase with the increasing of the molar ratio of CTAB to Co2+ (R-CTAB:Co). The Raman properties was investigated and the possible formation mechanism was supposed. (C) 2007 Elsevier B.V. All rights reserved.