To acquiring more insights into the relationship between the morphology and magnetic properties of magnetic nanocrystallites, uniform flowerlike Ni nanostructures with different branch lengths were fabricated via a simple solvothermal reduction route based on a series of comparative experiments The formation mechanism of the Ni flowers was proposed Moreover, the magnetic properties of the products were evaluated. Results indicate that the morphology of the Ni particles strongly depends on reaction temperature, and the branch length of the flowerlike Ni particles strongly depends on the initial concentration of Ni(2+) ions The flowerlike Ni particles with a longer branch length show higher coercivity value, which may be attributed to the peculiar microstructure We believe the present research may provide an ideal example for the synthesis of assembled magnetic nanostructures with controllable morphology and magnetic properties (C) 2010 Elsevier Ltd All rights reserved