The invention discloses a Cu-Ti amorphous alloy film and a preparation method thereof. The Cu-Ti amorphous alloy film is characterized in that the structural formula of the amorphous alloy film is CuxTi(100-x) (x is larger than or equal to 54 and smaller than or equal to 66), and x is the atomic percentage of the Cu element. Different from ordinary preparation technologies, the preparation method of the amorphous alloy film adopts an electron beam and resistance evaporation composite coating technology, during preparation, the metal Ti and the metal Cu adopt electron beam and resistance evaporation sources respectively for evaporation, no cooling device is required to be added to a substrate, the preparation technology is simplified, and the production cost is reduced. The prepared amorphous film is obvious in amorphous structure, and components and the size of the amorphous film can be controlled by adjusting the evaporation current and the evaporation time.