The invention discloses Rhopilema esculentum polypeptide composite tablet candy and a preparation method thereof. Rhopilema esculentum processed with alum three times is soaked, desalted, cleaned and ground into Rhopilema esculentum pulp, compound protease is used for enzymolysis and centrifugation of the Rhopilema esculentum pulp, a liquid supernatant obtained through enzymolysis is taken, concentrated, subjected to ultrafiltration and ground, and Rhopilema esculentum polypeptide powder is prepared; the Rhopilema esculentum polypeptide powder, xylitol, sorbitol, maltitol and magnesium stearate are mixed and ground, water is added, and the mixture is mixed, wetted, pressed into tablets, sterilized and packaged. The preparation method adopts a reasonable process and is simple in preparation and reliable to operate. The Rhopilema esculentum polypeptide composite tablet candy prepared with the method tastes unique and good, is convenient to take and has the efficacy of reducing the blood pressure.