||Double metal cyanide (DMC) catalysts are commonly exploited to produce high performance polyols via ring-opening polymerization of propylene oxide. Here, a series of DMC catalysts of the general formula Zn3[Co(CN)6]2•xZnCl2•yH2O•z[complexing agent (CA)] have been carried out by reacting aqueous solutions of zinc(II) chloride and potassium hexacyanocobaltate(III) in the presence of various CAs. The catalysts were well characterized by combining structure sensitive spectroscopies. The catalytic activity of the prepared catalysts was evaluated by changing the parameter such as amount of CA, the reaction temperature, the functionality of initiator, and the amount of initiator. The resultant polyols have moderate molecular weight (Mn = 3000-5500 g mol-1), narrow polydispersity index and low unsaturation level.