Carbonyl- and double-bond-containing cyclophosphazenes, having alpha,beta-unsaturated ketones residues linked via oxygen bridge to a cyclophosphazene skeleton, have been obtained by reactions of enolate forms of cyclohexanedione and acetylacetone with hexachlorocyclotriphosphazene. The respective mono-(I, II) and isomeric disubstituted (non-gem and gem) derivatives were isolated. Structural assignments were based on NMR (H-1 and P-31) and mass spectral data. The method provides a direct route to hitherto inaccessible unsaturated carbonyl containing cyclophosphazene derivatives which can serve for various addition reactions.