In order to clear and definite species of squash virus diseases in Beijing area and their main infection pathogens，this paper collected 84 squash samples with suspected virus-like symptoms during 2016-2017 from Beijing area，and carried out detection by RT-PCR used 6 pairs of specific virus primers．The results
showed that 79 samples were positive，among which Cucumber mosaic virus （CMV） had the highest detection rate -52.38%，followed by Zucchini yellow mosaic virus（ ZYMV） and Watermelon mosaic virus（ WMV）．Their detection rate were 44.01% and 14.29%，respectively．Other viruses were not yet detected．In addition，16.67% samples were mix-infected by 2 kinds of viruses．Mix infection of CMV and ZYMV took 7.14%．Mix infection of ZYMV and WMV took 9.52%．CMV was the prevalent pathogenic virus in Beijing area，where the mix infection of viruses on squash was existed．