Abstract: A novelmethod by combining vacuum d eposition and electrochemical reaction was developed toprepare metal-organic thin films.Ag-TCNQ film prepared by th is method shows an electrical bistable characteristic with a good homogeneity.The threshold voltage of the film is 4.5V and the switching time is lessthan 20ns.It a lso has a smooth surface morphology and a stoichiometric com-position.The method ishelpful for m aking micro-electronic devices,mo lectroic devices and high density memories.