The invention provides a preparation method of a medical nonwoven composite material. The preparation method comprises the following specific steps: (1) respectively weighing 30-50 parts by weight of poly(adipate-co-butylene terephthalate), 20-30 parts by weight of polylactic acid and 30-40 parts by weight of polypropylene, and fully mixing to obtain a mixture A; (2) blending the mixture obtained in the step (1) with 1-4 parts by weight of an antistatic agent and 0.5-2 parts by weight of an antibacterial agent, and extruding and pelletizing by a double-screw extruder to obtain a blend; (3) drying the blend obtained in the step (2) in vacuum, and heating, fusing, extruding, stretching, cooling and self-adhering the dried blend by the screw extruder to obtain a non-woven; and (4) spraying an anti-radiation layer to one side of the non-woven obtained in the step (3), and finally, drying and shaping in a drying oven. The medical nonwoven composite material has antibacterial property as well as anti-radiation and antistatic performance, and is mainly applied to manufacture of medical masks.