As means of the chemical fixation of carbon dioxide and the synthesis biodegradable polycarbonates, alternating copolymerizations of carbon dioxide with various epoxides such as cyclohexene oxide, cyclopetene oxide, 4-vinyl-1-cyclohexene-1,2epoxide, propylene oxide were investigated in the presence of multi and double metal cyanide catalyst (MMC and DMC). DMC catalysts were prepared by using K₃Co(CN)₆ and ZnCl₂ together with tertiary butyl alcohol and polytetramethylene ether glycol as complexing reagents. MMC catalyst was also prepared by incorporating additional K₂Ni(CN)₄ in DMC catalyst. All catalysts characterized by various spectroscopic methods were utilized for the copolymerization of epoxides and CO₂. All catalysts showed high activity to yield copolymers of narrow polydispersity and moderate molecular weight. MMC catalyst was much more reactive to CO₂ than DMC catalyst, resulting in higher carbonate linkage.