It has been known that,the novel coronavirus,2019-nCoV,which is considered similar to SARS-CoV,invades human cells via the receptor angiotensin converting enzyme Ⅱ (ACE2).Moreover,lung cells that have ACE2 expression may be the main target cells during 2019-nCoV infection.However,some patients also exhibit non-respiratory symptoms,such as kidney failure,implying that 2019-nCoV could also invade other organs.To construct a risk map of different human organs,we analyzed the single-cell RNA sequencing (scRNA-seq) datasets derived from major human physiological systems,including the respiratory,cardiovascular,digestive,and urinary systems.Through scRNA-seq data analyses,we identified the organs at risk,such as lung,heart,esophagus,kidney,bladder,and ileum,and located specific cell types (i.e.,type Ⅱ alveolar cells (AT2),myocardial cells,proximal tubule cells of the kidney,ileum and esophagus epithelial cells,and bladder urothelial cells),which are vulnerable to 2019-nCoV infection.Based on the findings,we constructed a risk map indicating the vulnerability of different organs to 2019-nCoV infection.This study may provide potential clues for further investigation of the pathogenesis and route of 2019-nCoV infection.