The invention provides an activated carbon filter of a water system for pharmacy, and relates to the field of water systems for pharmacy. The activated carbon filter of the water system for pharmacy comprises a filter body, wherein the bottom part of the interior of the filter body is fixedly connected with an installation seat; the top part of the installation seat is fixedly connected with a fixed box; the interior of the fixed box is fixedly connected with an activated carbon filtering layer; the top part of the fixed box is fixedly connected with a flow guide pipe; the top end of the flowguide pipe is clamped with the left side wall of the filter body; the left side of the filter body is fixedly connected with a water intake pipe which is communicated with the flow guide pipe. The activated carbon filter of the water system for pharmacy has the advantages that by arranging an air collecting box, a second fan and an ultraviolet sterilizing lamp, the collected air in the air collecting box is transferred and disinfected, an air leading nozzle is blocked by a plug, the air in the air collecting box is disinfected and sterilized by the ultraviolet sterilizing lamp, and the air isrespectively guided into a left cavity and a right cavity by a first air guide pipe and a second air guide pipe, so that the organic matters before filtering are respectively aerated and decomposed, and then the chloride after filtering is led with air and decomposed.