Magnetic Co chains with different morphologies have been successfully prepared with a facile solvothermal method by introducing 1,3-propanediamine (PDA). The prepared Co sub-micro chains possess particular magnetism and high thermal stability, which shows more practical and profound application. During the solvothermal process, the sizes and morphologies of Co chains are successfully controlled by adjusting the dosage of PDA and the reaction temperature. In particular, the growth of Co chains involves an oriented attachment process because the adjacent particles attach at a planar interface for removing the higher surface energy. Moreover, the different types of dislocation present at interface, while the densities of dislocation are increased with the rise in reaction temperature. (C) 2011 Elsevier B.V. All rights reserved.