ABSTRACTSARS-CoV-2 was reported to the WHO as an outbreak in Wuhan City, China on end of 2019, afterwards pandemic on the worldwide in 2020. The SARS-CoV-2 virus is less deadly, but far more transmissible. Therefore, it needs to detect and monitor quickly and simply on site to prevent SARS-CoV-2.If detecting coronaviruses including SARS-CoV-2, the real-time RT-PCR method is sensitive and specific for the unique target, however, it must take long time and labour that RNA is treated in advance, transcribed and amplified. Therefore, referenced previously report, in this study, we modified various methods to prove hypotheses the followed.Firstly, we hypothesized that real-time RT-PCR could be finished in very short time by the mobile real-time PCR device and one-step RT-PCR reagent. Secondly, we hypothesized that it was possible to perform RT-PCR utilizing the reagent as the above without RNA treatment in advance so called “direct”.Firstly, it was able to detect the positive control RNA of SARS-CoV-2 for less than 13.5 minutes by primer-probe referring to the CDC. Moreover, each detection value varied in accordance with each concentration (This correlation coefficient R2 > 0.95). Secondary, it was possible to detect human coronavirus 229E with direct RT-PCR. Furthermore, each detection value varied in accordance with each titer (TCID50 / mL) of human coronavirus 229E (This correlation coefficient R2 > 0.95).Considering the above, causing by utilizing the mobile real-time PCR device and the one-step real-time PCR reagent simultaneously following as: 1) It was possible to detect SARS-CoV-2 in very short time as compared to conventional method; 2) It was possible to detect human coronavirus quickly and simply with “direct”. For these reasons, we hypothesized that it is possible to detect SARS-CoV-2 quickly and simply by utilizing methods the above without treating RNA in advance. This hypothesis is our next try.STRENGTHS AND LIMITATIONS OF THIS STUDY*This study developed it possible to detect the positive control RNA of SARS-CoV-2 more quickly than previously, however couldn’t try to detect the genetic RNA.*This study proved clearly that the human coronavirus instead of SARS-CoV-2 could be detected simply without treating RNA in advance by the same method above.*This study couldn’t try to utilize the human specimens because of our institution limited.*This study could utilize the device and the reagents commercial and not especial.