A food poisoning case by the deer meat occurred in August, 2019 in Niigata prefecture in Japan. Thirty of 53 people showed digestive organ symptoms such as diarrhea, vomiting and the abdominal pain, and some people showed a symptom of the fever of a maximum of 38.2 degrees Celsius. Already-known bacteria and viruses were not detected in the food samples and patient feces. Parasitological test were performed molecularly and morphologically on the deer meat and patient feces. By PCR, 18S rRNA gene of genus Sarcocystis and mitochondrial cytochrome c oxidase subunit I gene (cox1) of Sarcocystis sp. were amplified from both the deer meat and patient feces. There were three types of Sarcocystis cysts in the deer meat, and DNA fragment length and sequence type of cox1 amplified by PCR were Type 1, Type 2, and Type 4 of Sarcocystis sp.. They were respectively presumed as S. japonica, S. cf. tarandi and S. pilosa by their molecular and morphological characteristics. These three Sacrocystis spp. showed a positive reaction of immunohistochemical staining of the toxic 15 kDa protein of S. fayeri. Therefore, the deer meat containing Sarcocystis cysts in this case was the causative suspected food of food poisoning.