COVID-19 is now widely spreading around the world as a global pandemic. In this report, we estimate the global tendency of COVID-19 and analyze the associated global epidemic risk, given that the status quo is continued without further measures being taken.The results show that the global 0 , excluding China, is estimated to be 2.49 (95% CI: 2.15 -2.92). The United States, Germany, Italy and Spain have peak values over 100,000. According to dynamical model and cluster analysis, we category the globe into four type regional epicenters of the outbreak: Southeast Asia extending southward to Oceania, the Middle East, Western Europe and North America. Among them, Western Europe will become the major center of the outbreak. The peak values in Germany, Italy and Spain are estimated to be 105,903, 127,283 and 152,539, respectively. The United States is the country with the most serious outbreak trend. Based on the current control measures by Mar. 27, 2020, the peak value in the United States will reach 400,892. Above all, if the current control measures are maintained, the cumulative number of patients worldwide will be 1, 442,523 (95% CI: 1,052,981,440). We also estimated the diagnosis rate, recovery rate and infection degree of each country or region, and use clustering algorithm to retrieve countries or regions with similar epidemic characteristics. Different suggestions are proposed for countries or regions in different clusters.