There has been no report on Chronic wasting disease (CWD) cases in Japan to date; however, there is concern about the geographic spread of CWD. To clarify the CWD status in Japan, we conducted CWD monitoring using real-time quaking-induced conversion (RT-QuIC) assay which can detect the low level of CWD prions. A total of 690 obex samples collected from sika deer and Reeves's muntjac in Hokkaido and Honshu was tested for CWD prions. No CWDpositive cases were found, suggesting that CWD is nonexistent in Japan. Our results also indicate that RT-QuIC assay is useful for continuous monitoring of CWD. Furthermore, nucleotide sequence analysis of the PrP gene revealed sika deer in Japan harbor CWD susceptible allele. KEY WORDS: chronic wasting disease, prion, prion protein, real-time quaking-induced conversion, scrapie Chronic wasting disease (CWD) is a prion disease in the wild cervid, which is progressive and ultimately fatal. Since CWD was first identified in a group of captive mule deer in 1967, CWD cases in cervids such, as white tailed deer, mule deer, elk, and reindeer have been disclosed in the U.S.A., Canada, South Korea [5], and recently in Scandinavian countries [12,21]. Unlike other prion diseases, CWD prions, the causative agents of CWD, are secreted from infected animals into body fluids and excretions such as saliva, urine, and feces [14]. Compared with bovine spongiform encephalopathy (BSE), CWD transmission does not occur in mice expressing human PrP [11]; however, the zoonotic potential of CWD cannot be ignored as CWD prions can be transmitted experimentally to several animals including the squirrel monkey [18].Recently, venison consumption in Japan is getting popular yearly. From 2017 to 2019, the amount of processed sika deer (Cervus Nippon) meat at the slaughterhouses increases by nearly 150 tons every year in Japan [16]. Therefore, clarifying the CWD status in Japan is important