The invention relates to a traditional Chinese medicine detoxification pill for treating pituitary adenoma and a preparation method thereof. The detoxification pill comprises the following components: toad venom, calomel, verdigris, crystalline mirabilite, frankincense stir-baked with vinegar, myrrh stir-baked with vinegar, chalcanthite, realgar, cinnabar and live snail, wherein each component accounts for 1-3 parts by weight. The preparation method of the detoxification pill comprises the following steps: selecting high-quality and clean toad venom, calomel, verdigris, crystalline mirabilite, frankincense stir-baked with vinegar, myrrh stir-baked with vinegar, chalcanthite, realgar, cinnabar and live snail according to the parts by weight, co-grinding the medicines in addition to snail and toad venom to obtain powder, and loading into a disinfection container for later use; firstly placing snail into the disinfection container for mashing, co-grinding with toad venom, adjusting the viscosity, then adding the powder, uniformly blending together and then making the pill. The detoxification pill has the particle size of about 3.0mm-5.0mm and is dried in the shade and stored.