A compound ambroxol hydrochloride composition and a preparation method therefor, which relate to the field of medicine. 0.1%-99.9% by mass of ambroxol hydrochloride and 99.9%-0.1% by mass of scopolamine serving as main ingredients and mannitol are added into water for injection； stir to dissolve, then adjusting to pH 5.0 by adding an NaOH solution； add 0.1% of activated carbon with stirring for 30 minutes； filter out the activated carbon, and then filtering the liquid with 0.45 μm and 0.22 μm microporous filter membranes； fill the filtered liquid into a large plate or a vial； send into a lyophilizer, cool to −40° C., and hold the temperature for 2 hours； warm to −5° C. to 0° C. slowly to lyophilize the liquid, heat to 35° C., and hold the temperature for 3 hours； take out of the lyophilizer after lyophilizing to obtain a lyophilized powder injection containing ambroxol hydrochloride and scopolamine； crush the lyophilized powder injection under a sterile conditions, and sieve with a 180-mesh sieve to obtain sterile lyophilized powder containing ambroxol hydrochloride and scopolamine； and prepare various dosage forms by using the lyophilized powder as a raw material.
