A topical patch preparation for treatment of toxicity of mosquitoes proposed by the present invention includes: a back sheet (100) and an adhesive heating element (200) stacked and attached to the lower surface of the back sheet (100) and including exothermic compositions mixed therein to generate heat. Thus, the topical patch preparation may decompose the toxicity of mosquitoes caused by a mosquito bite simply by using heat without chemicals or drugs so as to immediately relieve itching and swelling.