The synthesis of iron oxide particles was carried out by the hydrolysis of iron tri-n-butoxide in an octanol/acetonitrile solution. The morphology of the particles formed was found to depend on composition of the mixture of solvents used and also on the method of its addition, i.e. either instantaneous or continuous. The data of apparent reaction rate revealed that the selection of reaction conditions controlling the reaction rate was the most important factor for achieving formation of monodispersed particles. These particles were subsequently used for preparation of magnetic particles by de-oxidation process.